21347621867 has 24 divisors (see below), whose sum is σ = 25285140720. Its totient is φ = 17903160000.

The previous prime is 21347621851. The next prime is 21347621873. The reversal of 21347621867 is 76812674312.

It is not a de Polignac number, because 21347621867 - 2⁴ = 21347621851 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21347621767) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3537809 + ... + 3543837.

It is an arithmetic number, because the mean of its divisors is an integer number (1053547530).

Almost surely, 2^21347621867 is an apocalyptic number.

21347621867 is a deficient number, since it is larger than the sum of its proper divisors (3937518853).

21347621867 is a wasteful number, since it uses less digits than its factorization.

21347621867 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8315 (or 8304 counting only the distinct ones).

The product of its digits is 677376, while the sum is 47.

The spelling of 21347621867 in words is "twenty-one billion, three hundred forty-seven million, six hundred twenty-one thousand, eight hundred sixty-seven".