21012174 has 24 divisors (see below), whose sum is σ = 46152912. Its totient is φ = 6907680.

The previous prime is 21012161. The next prime is 21012181. The reversal of 21012174 is 47121012.

It is a super-2 number, since 2×21012174² = 883022912412552, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6682 + ... + 9309.

It is an arithmetic number, because the mean of its divisors is an integer number (1923038).

Almost surely, 2^21012174 is an apocalyptic number.

21012174 is an abundant number, since it is smaller than the sum of its proper divisors (25140738).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21012174 is a wasteful number, since it uses less digits than its factorization.

21012174 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16072 (or 16069 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 18.

The square root of 21012174 is about 4583.9037948020. The cubic root of 21012174 is about 275.9457202646.

Adding to 21012174 its reverse (47121012), we get a palindrome (68133186).

The spelling of 21012174 in words is "twenty-one million, twelve thousand, one hundred seventy-four".