21531315010 has 32 divisors (see below), whose sum is σ = 39010833792. Its totient is φ = 8556038400.

The previous prime is 21531315007. The next prime is 21531315011. The reversal of 21531315010 is 1051313512.

It is not an unprimeable number, because it can be changed into a prime (21531315011) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4675369 + ... + 4679971.

It is an arithmetic number, because the mean of its divisors is an integer number (1219088556).

Almost surely, 2^21531315010 is an apocalyptic number.

21531315010 is a deficient number, since it is larger than the sum of its proper divisors (17479518782).

21531315010 is a wasteful number, since it uses less digits than its factorization.

21531315010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7578.

The product of its (nonzero) digits is 450, while the sum is 22.

Adding to 21531315010 its reverse (1051313512), we get a palindrome (22582628522).

The spelling of 21531315010 in words is "twenty-one billion, five hundred thirty-one million, three hundred fifteen thousand, ten".