21401379 has 12 divisors (see below), whose sum is σ = 30956016. Its totient is φ = 14247792.

The previous prime is 21401363. The next prime is 21401389. The reversal of 21401379 is 97310412.

It is not a de Polignac number, because 21401379 - 2⁴ = 21401363 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (21401389) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8449 + ... + 10685.

It is an arithmetic number, because the mean of its divisors is an integer number (2579668).

Almost surely, 2^21401379 is an apocalyptic number.

21401379 is a deficient number, since it is larger than the sum of its proper divisors (9554637).

21401379 is a wasteful number, since it uses less digits than its factorization.

21401379 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3306 (or 3303 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 21401379 is about 4626.1624485096. The cubic root of 21401379 is about 277.6390732165.

The spelling of 21401379 in words is "twenty-one million, four hundred one thousand, three hundred seventy-nine".