21373278 has 16 divisors (see below), whose sum is σ = 42808080. Its totient is φ = 7114176.

The previous prime is 21373277. The next prime is 21373327. The reversal of 21373278 is 87237312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21373277) by changing a digit.

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, 2826 + ... + 7122.

It is an arithmetic number, because the mean of its divisors is an integer number (2675505).

Almost surely, 2^21373278 is an apocalyptic number.

21373278 is an abundant number, since it is smaller than the sum of its proper divisors (21434802).

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

21373278 is a wasteful number, since it uses less digits than its factorization.

21373278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5131.

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

The square root of 21373278 is about 4623.1242682844. The cubic root of 21373278 is about 277.5175023455.

The spelling of 21373278 in words is "twenty-one million, three hundred seventy-three thousand, two hundred seventy-eight".