21264737 has 8 divisors (see below), whose sum is σ = 22936704. Its totient is φ = 19597968.

The previous prime is 21264709. The next prime is 21264769. The reversal of 21264737 is 73746212.

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

It is not a de Polignac number, because 21264737 - 2¹⁰ = 21263713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21264787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13598 + ... + 15080.

It is an arithmetic number, because the mean of its divisors is an integer number (2867088).

Almost surely, 2^21264737 is an apocalyptic number.

It is an amenable number.

21264737 is a deficient number, since it is larger than the sum of its proper divisors (1671967).

21264737 is a wasteful number, since it uses less digits than its factorization.

21264737 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2599.

The product of its digits is 14112, while the sum is 32.

The square root of 21264737 is about 4611.3704036870. The cubic root of 21264737 is about 277.0469278015.

The spelling of 21264737 in words is "twenty-one million, two hundred sixty-four thousand, seven hundred thirty-seven".