21612231456057 has 216 divisors, whose sum is σ = 37306181083392. Its totient is φ = 12403260820800.

The previous prime is 21612231456041. The next prime is 21612231456059. The reversal of 21612231456057 is 75065413221612.

21612231456057 is a `hidden beast` number, since 2 + 1 + 6 + 1 + 2 + 2 + 31 + 4 + 5 + 605 + 7 = 666.

It is not a de Polignac number, because 21612231456057 - 2⁴ = 21612231456041 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21612231456059) by changing a digit.

It is a polite number, since it can be written in 215 ways as a sum of consecutive naturals, for example, 4942195723 + ... + 4942200095.

It is an arithmetic number, because the mean of its divisors is an integer number (172713801312).

Almost surely, 2^{21612231456057} is an apocalyptic number.

21612231456057 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

21612231456057 is a deficient number, since it is larger than the sum of its proper divisors (15693949627335).

21612231456057 is an frugal number, since it uses more digits than its factorization.

21612231456057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4533 (or 4465 counting only the distinct ones).

The product of its (nonzero) digits is 604800, while the sum is 45.

Adding to 21612231456057 its reverse (75065413221612), we get a palindrome (96677644677669).

The spelling of 21612231456057 in words is "twenty-one trillion, six hundred twelve billion, two hundred thirty-one million, four hundred fifty-six thousand, fifty-seven".