21057295 has 16 divisors (see below), whose sum is σ = 29003328. Its totient is φ = 14376960.

The previous prime is 21057287. The next prime is 21057299. The reversal of 21057295 is 59275012.

It is not a de Polignac number, because 21057295 - 2³ = 21057287 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21057299) 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, 7825 + ... + 10165.

It is an arithmetic number, because the mean of its divisors is an integer number (1812708).

Almost surely, 2^21057295 is an apocalyptic number.

21057295 is a deficient number, since it is larger than the sum of its proper divisors (7946033).

21057295 is a wasteful number, since it uses less digits than its factorization.

21057295 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2610.

The product of its (nonzero) digits is 6300, while the sum is 31.

The square root of 21057295 is about 4588.8228337995. The cubic root of 21057295 is about 276.1430986222.

The spelling of 21057295 in words is "twenty-one million, fifty-seven thousand, two hundred ninety-five".