21264741 has 16 divisors (see below), whose sum is σ = 31574400. Its totient is φ = 14144544.

The previous prime is 21264709. The next prime is 21264769. The reversal of 21264741 is 14746212.

21264741 is a `hidden beast` number, since 2 + 12 + 647 + 4 + 1 = 666.

It is not a de Polignac number, because 21264741 - 2⁵ = 21264709 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21264241) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22680 + ... + 23598.

It is an arithmetic number, because the mean of its divisors is an integer number (1973400).

Almost surely, 2^21264741 is an apocalyptic number.

It is an amenable number.

21264741 is a deficient number, since it is larger than the sum of its proper divisors (10309659).

21264741 is an equidigital number, since it uses as much as digits as its factorization.

21264741 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1785 (or 1779 counting only the distinct ones).

The product of its digits is 2688, while the sum is 27.

The square root of 21264741 is about 4611.3708373975. The cubic root of 21264741 is about 277.0469451728.

The spelling of 21264741 in words is "twenty-one million, two hundred sixty-four thousand, seven hundred forty-one".