21375711 has 48 divisors (see below), whose sum is σ = 37428480. Its totient is φ = 12020400.

The previous prime is 21375661. The next prime is 21375721. The reversal of 21375711 is 11757312.

It is a happy number.

It is not a de Polignac number, because 21375711 - 2⁹ = 21375199 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21375721) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 141486 + ... + 141636.

It is an arithmetic number, because the mean of its divisors is an integer number (779760).

Almost surely, 2^21375711 is an apocalyptic number.

21375711 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21375711 is a deficient number, since it is larger than the sum of its proper divisors (16052769).

21375711 is a wasteful number, since it uses less digits than its factorization.

21375711 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281 (or 268 counting only the distinct ones).

The product of its digits is 1470, while the sum is 27.

The square root of 21375711 is about 4623.3873945409. The cubic root of 21375711 is about 277.5280322303.

The spelling of 21375711 in words is "twenty-one million, three hundred seventy-five thousand, seven hundred eleven".