1645210400 has 72 divisors (see below), whose sum is σ = 4023586224. Its totient is φ = 656902400.

The previous prime is 1645210387. The next prime is 1645210409. The reversal of 1645210400 is 40125461.

It is not an unprimeable number, because it can be changed into a prime (1645210409) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 544895 + ... + 547905.

It is an arithmetic number, because the mean of its divisors is an integer number (55883142).

Almost surely, 2^1645210400 is an apocalyptic number.

1645210400 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 1645210400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2011793112).

1645210400 is an abundant number, since it is smaller than the sum of its proper divisors (2378375824).

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

1645210400 is a wasteful number, since it uses less digits than its factorization.

1645210400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3714 (or 3701 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 1645210400 is about 40561.1932763325. The cubic root of 1645210400 is about 1180.5212673491.

Adding to 1645210400 its reverse (40125461), we get a palindrome (1685335861).

The spelling of 1645210400 in words is "one billion, six hundred forty-five million, two hundred ten thousand, four hundred".