20657402 has 4 divisors (see below), whose sum is σ = 30986106. Its totient is φ = 10328700.

The previous prime is 20657401. The next prime is 20657407. The reversal of 20657402 is 20475602.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 16491721 + 4165681 = 4061^2 + 2041^2 .

It is not an unprimeable number, because it can be changed into a prime (20657401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5164349 + ... + 5164352.

Almost surely, 2^20657402 is an apocalyptic number.

20657402 is a deficient number, since it is larger than the sum of its proper divisors (10328704).

20657402 is a wasteful number, since it uses less digits than its factorization.

20657402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10328703.

The product of its (nonzero) digits is 3360, while the sum is 26.

The square root of 20657402 is about 4545.0414739582. The cubic root of 20657402 is about 274.3838635548.

The spelling of 20657402 in words is "twenty million, six hundred fifty-seven thousand, four hundred two".