21506053510 has 16 divisors (see below), whose sum is σ = 38716763616. Its totient is φ = 8601117568.

The previous prime is 21506053489. The next prime is 21506053619. The reversal of 21506053510 is 1535060512.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 92242 + ... + 226981.

It is an arithmetic number, because the mean of its divisors is an integer number (2419797726).

Almost surely, 2^21506053510 is an apocalyptic number.

21506053510 is a deficient number, since it is larger than the sum of its proper divisors (17210710106).

21506053510 is a wasteful number, since it uses less digits than its factorization.

21506053510 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 325967.

The product of its (nonzero) digits is 4500, while the sum is 28.

The spelling of 21506053510 in words is "twenty-one billion, five hundred six million, fifty-three thousand, five hundred ten".