21310641515 has 8 divisors (see below), whose sum is σ = 25586024688. Its totient is φ = 17039676640.

The previous prime is 21310641497. The next prime is 21310641553. The reversal of 21310641515 is 51514601312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-21310641515 is a prime.

It is a Duffinian 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, 1093952 + ... + 1113261.

It is an arithmetic number, because the mean of its divisors is an integer number (3198253086).

Almost surely, 2^21310641515 is an apocalyptic number.

21310641515 is a deficient number, since it is larger than the sum of its proper divisors (4275383173).

21310641515 is a wasteful number, since it uses less digits than its factorization.

21310641515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2209149.

The product of its (nonzero) digits is 3600, while the sum is 29.

The spelling of 21310641515 in words is "twenty-one billion, three hundred ten million, six hundred forty-one thousand, five hundred fifteen".