21379012 has 12 divisors (see below), whose sum is σ = 37610496. Its totient is φ = 10633160.

The previous prime is 21378997. The next prime is 21379019. The reversal of 21379012 is 21097312.

It is a super-2 number, since 2×21379012² = 914124308192288, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21379019) 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, 13228 + ... + 14755.

It is an arithmetic number, because the mean of its divisors is an integer number (3134208).

Almost surely, 2^21379012 is an apocalyptic number.

It is an amenable number.

21379012 is a deficient number, since it is larger than the sum of its proper divisors (16231484).

21379012 is a wasteful number, since it uses less digits than its factorization.

21379012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28178 (or 28176 counting only the distinct ones).

The product of its (nonzero) digits is 756, while the sum is 25.

The square root of 21379012 is about 4623.7443700966. The cubic root of 21379012 is about 277.5423174920.

The spelling of 21379012 in words is "twenty-one million, three hundred seventy-nine thousand, twelve".