21732378 has 48 divisors (see below), whose sum is σ = 46823616. Its totient is φ = 6719680.

The previous prime is 21732353. The next prime is 21732383. The reversal of 21732378 is 87323712.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 130051 + ... + 130217.

It is an arithmetic number, because the mean of its divisors is an integer number (975492).

Almost surely, 2^21732378 is an apocalyptic number.

21732378 is an abundant number, since it is smaller than the sum of its proper divisors (25091238).

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

21732378 is a wasteful number, since it uses less digits than its factorization.

21732378 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 259 (or 236 counting only the distinct ones).

The product of its digits is 14112, while the sum is 33.

The square root of 21732378 is about 4661.7998670042. The cubic root of 21732378 is about 279.0631015659.

The spelling of 21732378 in words is "twenty-one million, seven hundred thirty-two thousand, three hundred seventy-eight".