21386374 has 8 divisors (see below), whose sum is σ = 33966648. Its totient is φ = 10064160.

The previous prime is 21386359. The next prime is 21386399. The reversal of 21386374 is 47368312.

It is a happy number.

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

It is a Harshad number since it is a multiple of its sum of digits (34), and also a Moran number because the ratio is a prime number: 629011 = 21386374 / (2 + 1 + 3 + 8 + 6 + 3 + 7 + 4).

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, 314472 + ... + 314539.

It is an arithmetic number, because the mean of its divisors is an integer number (4245831).

Almost surely, 2^21386374 is an apocalyptic number.

21386374 is a deficient number, since it is larger than the sum of its proper divisors (12580274).

21386374 is a wasteful number, since it uses less digits than its factorization.

21386374 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 629030.

The product of its digits is 24192, while the sum is 34.

The square root of 21386374 is about 4624.5404095975. The cubic root of 21386374 is about 277.5741716620.

The spelling of 21386374 in words is "twenty-one million, three hundred eighty-six thousand, three hundred seventy-four".