21325857 has 8 divisors (see below), whose sum is σ = 32496576. Its totient is φ = 12186192.

The previous prime is 21325819. The next prime is 21325891. The reversal of 21325857 is 75852312.

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

It is not a de Polignac number, because 21325857 - 2¹⁵ = 21293089 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21325897) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 507738 + ... + 507779.

It is an arithmetic number, because the mean of its divisors is an integer number (4062072).

Almost surely, 2^21325857 is an apocalyptic number.

It is an amenable number.

21325857 is a deficient number, since it is larger than the sum of its proper divisors (11170719).

21325857 is a wasteful number, since it uses less digits than its factorization.

21325857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1015527.

The product of its digits is 16800, while the sum is 33.

The square root of 21325857 is about 4617.9927457717. The cubic root of 21325857 is about 277.3121072047.

The spelling of 21325857 in words is "twenty-one million, three hundred twenty-five thousand, eight hundred fifty-seven".