21167821075 has 12 divisors (see below), whose sum is σ = 26617791888. Its totient is φ = 16695744800.

The previous prime is 21167821063. The next prime is 21167821153. The reversal of 21167821075 is 57012876112.

It is not a de Polignac number, because 21167821075 - 2⁵ = 21167821043 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5960992 + ... + 5964541.

It is an arithmetic number, because the mean of its divisors is an integer number (2218149324).

Almost surely, 2^21167821075 is an apocalyptic number.

21167821075 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21167821075 is a deficient number, since it is larger than the sum of its proper divisors (5449970813).

21167821075 is a wasteful number, since it uses less digits than its factorization.

21167821075 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11925614 (or 11925609 counting only the distinct ones).

The product of its (nonzero) digits is 47040, while the sum is 40.

The spelling of 21167821075 in words is "twenty-one billion, one hundred sixty-seven million, eight hundred twenty-one thousand, seventy-five".