21257254 has 8 divisors (see below), whose sum is σ = 32564448. Its totient is φ = 10402440.

The previous prime is 21257251. The next prime is 21257273. The reversal of 21257254 is 45275212.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21257251) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 112977 + ... + 113164.

It is an arithmetic number, because the mean of its divisors is an integer number (4070556).

Almost surely, 2^21257254 is an apocalyptic number.

21257254 is a deficient number, since it is larger than the sum of its proper divisors (11307194).

21257254 is a wasteful number, since it uses less digits than its factorization.

21257254 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226190.

The product of its digits is 5600, while the sum is 28.

The square root of 21257254 is about 4610.5589682814. The cubic root of 21257254 is about 277.0144266490.

The spelling of 21257254 in words is "twenty-one million, two hundred fifty-seven thousand, two hundred fifty-four".