21515523404012 has 12 divisors (see below), whose sum is σ = 41075090135016. Its totient is φ = 9779783365440.

The previous prime is 21515523403991. The next prime is 21515523404021. The reversal of 21515523404012 is 21040432551512.

It is a super-2 number, since 2×21515523404012² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 244494584093 + ... + 244494584180.

It is an arithmetic number, because the mean of its divisors is an integer number (3422924177918).

Almost surely, 2^{21515523404012} is an apocalyptic number.

21515523404012 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21515523404012 is a deficient number, since it is larger than the sum of its proper divisors (19559566731004).

21515523404012 is a wasteful number, since it uses less digits than its factorization.

21515523404012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 488989168288 (or 488989168286 counting only the distinct ones).

The product of its (nonzero) digits is 48000, while the sum is 35.

Adding to 21515523404012 its reverse (21040432551512), we get a palindrome (42555955955524).

The spelling of 21515523404012 in words is "twenty-one trillion, five hundred fifteen billion, five hundred twenty-three million, four hundred four thousand, twelve".