21265465 has 32 divisors (see below), whose sum is σ = 29473920. Its totient is φ = 14598144.

The previous prime is 21265459. The next prime is 21265523. The reversal of 21265465 is 56456212.

It is a 5-Lehmer number, since φ(21265465) divides (21265465-1)⁵.

It is a cyclic number.

It is not a de Polignac number, because 21265465 - 2⁷ = 21265337 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 82617 + ... + 82873.

It is an arithmetic number, because the mean of its divisors is an integer number (921060).

Almost surely, 2^21265465 is an apocalyptic number.

It is an amenable number.

21265465 is a deficient number, since it is larger than the sum of its proper divisors (8208455).

21265465 is a wasteful number, since it uses less digits than its factorization.

21265465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 361.

The product of its digits is 14400, while the sum is 31.

The square root of 21265465 is about 4611.4493383317. The cubic root of 21265465 is about 277.0500893402.

The spelling of 21265465 in words is "twenty-one million, two hundred sixty-five thousand, four hundred sixty-five".