21237470 has 8 divisors (see below), whose sum is σ = 38227464. Its totient is φ = 8494984.

The previous prime is 21237431. The next prime is 21237493. The reversal of 21237470 is 7473212.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1061864 + ... + 1061883.

It is an arithmetic number, because the mean of its divisors is an integer number (4778433).

Almost surely, 2^21237470 is an apocalyptic number.

21237470 is a deficient number, since it is larger than the sum of its proper divisors (16989994).

21237470 is a wasteful number, since it uses less digits than its factorization.

21237470 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2123754.

The product of its (nonzero) digits is 2352, while the sum is 26.

The square root of 21237470 is about 4608.4129589263. The cubic root of 21237470 is about 276.9284614140.

The spelling of 21237470 in words is "twenty-one million, two hundred thirty-seven thousand, four hundred seventy".