1645401600 has 540 divisors, whose sum is σ = 6383573196. Its totient is φ = 419696640.

The previous prime is 1645401587. The next prime is 1645401613. The reversal of 1645401600 is 61045461.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

1645401600 is a `hidden beast` number, since 1 + 6 + 4 + 54 + 0 + 1 + 600 = 666.

It is an interprime number because it is at equal distance from previous prime (1645401587) and next prime (1645401613).

It is a tau number, because it is divible by the number of its divisors (540).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 71539189 + ... + 71539211.

Almost surely, 2^1645401600 is an apocalyptic number.

1645401600 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1645401600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3191786598).

1645401600 is an abundant number, since it is smaller than the sum of its proper divisors (4738171596).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1645401600 is an frugal number, since it uses more digits than its factorization.

1645401600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89 (or 33 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 1645401600 is about 40563.5501404894. The cubic root of 1645401600 is about 1180.5669974521.

The spelling of 1645401600 in words is "one billion, six hundred forty-five million, four hundred one thousand, six hundred".