21601630365200 has 60 divisors (see below), whose sum is σ = 51900542322708. Its totient is φ = 8640215040000.

The previous prime is 21601630365169. The next prime is 21601630365223. The reversal of 21601630365200 is 256303610612.

It can be written as a sum of positive squares in 6 ways, for example, as 6353948655616 + 15247681709584 = 2520704^2 + 3904828^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6609200 + ... + 9321200.

Almost surely, 2^{21601630365200} is an apocalyptic number.

21601630365200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21601630365200 is an abundant number, since it is smaller than the sum of its proper divisors (30298911957508).

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

21601630365200 is a wasteful number, since it uses less digits than its factorization.

21601630365200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2731932 (or 2731921 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 35.

Adding to 21601630365200 its reverse (256303610612), we get a palindrome (21857933975812).

The spelling of 21601630365200 in words is "twenty-one trillion, six hundred one billion, six hundred thirty million, three hundred sixty-five thousand, two hundred".