21264051 has 16 divisors (see below), whose sum is σ = 29069568. Its totient is φ = 13821600.

The previous prime is 21264037. The next prime is 21264053. The reversal of 21264051 is 15046212.

It is not a de Polignac number, because 21264051 - 2⁶ = 21263987 is a prime.

It is a super-3 number, since 3×21264051³ (a number of 23 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (21264053) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23530 + ... + 24416.

It is an arithmetic number, because the mean of its divisors is an integer number (1816848).

Almost surely, 2^21264051 is an apocalyptic number.

21264051 is a deficient number, since it is larger than the sum of its proper divisors (7805517).

21264051 is a wasteful number, since it uses less digits than its factorization.

21264051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1082.

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 21264051 is about 4611.2960217275. The cubic root of 21264051 is about 277.0439485933.

The spelling of 21264051 in words is "twenty-one million, two hundred sixty-four thousand, fifty-one".