21272378 has 8 divisors (see below), whose sum is σ = 33295968. Its totient is φ = 10173724.

The previous prime is 21272371. The next prime is 21272411. The reversal of 21272378 is 87327212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (21272371) 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, 231176 + ... + 231267.

It is an arithmetic number, because the mean of its divisors is an integer number (4161996).

Almost surely, 2^21272378 is an apocalyptic number.

21272378 is a deficient number, since it is larger than the sum of its proper divisors (12023590).

21272378 is a wasteful number, since it uses less digits than its factorization.

21272378 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 462468.

The product of its digits is 9408, while the sum is 32.

The square root of 21272378 is about 4612.1988248557. The cubic root of 21272378 is about 277.0801073336.

The spelling of 21272378 in words is "twenty-one million, two hundred seventy-two thousand, three hundred seventy-eight".