1620401244 has 192 divisors, whose sum is σ = 5179023360. Its totient is φ = 381300480.

The previous prime is 1620401227. The next prime is 1620401269. The reversal of 1620401244 is 4421040261.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 401782 + ... + 405794.

It is an arithmetic number, because the mean of its divisors is an integer number (26974080).

Almost surely, 2^1620401244 is an apocalyptic number.

1620401244 is a gapful number since it is divisible by the number (14) 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 1620401244, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2589511680).

1620401244 is an abundant number, since it is smaller than the sum of its proper divisors (3558622116).

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

1620401244 is a wasteful number, since it uses less digits than its factorization.

1620401244 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4080 (or 4078 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 24.

The square root of 1620401244 is about 40254.2077800570. The cubic root of 1620401244 is about 1174.5572483681.

The spelling of 1620401244 in words is "one billion, six hundred twenty million, four hundred one thousand, two hundred forty-four".