21215947369516 has 24 divisors (see below), whose sum is σ = 37154815457760. Its totient is φ = 10600286524800.

The previous prime is 21215947369501. The next prime is 21215947369579. The reversal of 21215947369516 is 61596374951212.

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, 137768601 + ... + 137922511.

It is an arithmetic number, because the mean of its divisors is an integer number (1548117310740).

Almost surely, 2^{21215947369516} is an apocalyptic number.

It is an amenable number.

21215947369516 is a deficient number, since it is larger than the sum of its proper divisors (15938868088244).

21215947369516 is a wasteful number, since it uses less digits than its factorization.

21215947369516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 178665 (or 178663 counting only the distinct ones).

The product of its digits is 24494400, while the sum is 61.

The spelling of 21215947369516 in words is "twenty-one trillion, two hundred fifteen billion, nine hundred forty-seven million, three hundred sixty-nine thousand, five hundred sixteen".