21714745 has 16 divisors (see below), whose sum is σ = 28823760. Its totient is φ = 15600384.

The previous prime is 21714733. The next prime is 21714779. The reversal of 21714745 is 54741712.

It can be written as a sum of positive squares in 8 ways, for example, as 2319529 + 19395216 = 1523^2 + 4404^2 .

It is not a de Polignac number, because 21714745 - 2⁵ = 21714713 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2110 + ... + 6919.

It is an arithmetic number, because the mean of its divisors is an integer number (1801485).

Almost surely, 2^21714745 is an apocalyptic number.

It is an amenable number.

21714745 is a deficient number, since it is larger than the sum of its proper divisors (7109015).

21714745 is a wasteful number, since it uses less digits than its factorization.

21714745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9084.

The product of its digits is 7840, while the sum is 31.

The square root of 21714745 is about 4659.9082608996. The cubic root of 21714745 is about 278.9876066659.

The spelling of 21714745 in words is "twenty-one million, seven hundred fourteen thousand, seven hundred forty-five".