21074351 has 4 divisors (see below), whose sum is σ = 21135432. Its totient is φ = 21013272.

The previous prime is 21074323. The next prime is 21074353. The reversal of 21074351 is 15347012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21074351 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 (21074353) 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, 30020 + ... + 30713.

It is an arithmetic number, because the mean of its divisors is an integer number (5283858).

Almost surely, 2^21074351 is an apocalyptic number.

21074351 is a deficient number, since it is larger than the sum of its proper divisors (61081).

21074351 is an equidigital number, since it uses as much as digits as its factorization.

21074351 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61080.

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 21074351 is about 4590.6808863174. The cubic root of 21074351 is about 276.2176353504.

The spelling of 21074351 in words is "twenty-one million, seventy-four thousand, three hundred fifty-one".