21088012 has 24 divisors (see below), whose sum is σ = 40637520. Its totient is φ = 9495360.

The previous prime is 21088009. The next prime is 21088013.

21088012 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×21088012² = 889408500224288, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is not an unprimeable number, because it can be changed into a prime (21088013) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2598 + ... + 6994.

It is an arithmetic number, because the mean of its divisors is an integer number (1693230).

Almost surely, 2^21088012 is an apocalyptic number.

21088012 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21088012 is a deficient number, since it is larger than the sum of its proper divisors (19549508).

21088012 is a wasteful number, since it uses less digits than its factorization.

21088012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4521 (or 4519 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 22.

The square root of 21088012 is about 4592.1685509136. The cubic root of 21088012 is about 276.2773065286.

The spelling of 21088012 in words is "twenty-one million, eighty-eight thousand, twelve".