21132678 has 16 divisors (see below), whose sum is σ = 48303360. Its totient is φ = 6037896.

The previous prime is 21132667. The next prime is 21132689. The reversal of 21132678 is 87623112.

It is an interprime number because it is at equal distance from previous prime (21132667) and next prime (21132689).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 251538 + ... + 251621.

It is an arithmetic number, because the mean of its divisors is an integer number (3018960).

Almost surely, 2^21132678 is an apocalyptic number.

21132678 is an abundant number, since it is smaller than the sum of its proper divisors (27170682).

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

21132678 is a wasteful number, since it uses less digits than its factorization.

21132678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 503171.

The product of its digits is 4032, while the sum is 30.

The square root of 21132678 is about 4597.0292581188. The cubic root of 21132678 is about 276.4722276987.

The spelling of 21132678 in words is "twenty-one million, one hundred thirty-two thousand, six hundred seventy-eight".