21292065 has 40 divisors (see below), whose sum is σ = 40191360. Its totient is φ = 10754208.

The previous prime is 21292039. The next prime is 21292067. The reversal of 21292065 is 56029212.

It is not a de Polignac number, because 21292065 - 2⁷ = 21291937 is a prime.

It is a super-4 number, since 4×21292065⁴ (a number of 30 digits) contains 4444 as substring.

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21292067) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 6312 + ... + 9078.

It is an arithmetic number, because the mean of its divisors is an integer number (1004784).

Almost surely, 2^21292065 is an apocalyptic number.

It is an amenable number.

21292065 is a deficient number, since it is larger than the sum of its proper divisors (18899295).

21292065 is a wasteful number, since it uses less digits than its factorization.

21292065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2803 (or 2794 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 21292065 is about 4614.3325627874. The cubic root of 21292065 is about 277.1655576479.

The spelling of 21292065 in words is "twenty-one million, two hundred ninety-two thousand, sixty-five".