21011512522 has 64 divisors (see below), whose sum is σ = 43180704000. Its totient is φ = 7556552640.

The previous prime is 21011512481. The next prime is 21011512567. The reversal of 21011512522 is 22521511012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 21011512493 and 21011512502.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8997 + ... + 205192.

It is an arithmetic number, because the mean of its divisors is an integer number (674698500).

Almost surely, 2^21011512522 is an apocalyptic number.

21011512522 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21011512522 is an abundant number, since it is smaller than the sum of its proper divisors (22169191478).

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

21011512522 is a wasteful number, since it uses less digits than its factorization.

21011512522 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214236 (or 214222 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 22.

The spelling of 21011512522 in words is "twenty-one billion, eleven million, five hundred twelve thousand, five hundred twenty-two".