20657738 has 4 divisors (see below), whose sum is σ = 30986610. Its totient is φ = 10328868.

The previous prime is 20657717. The next prime is 20657743. The reversal of 20657738 is 83775602.

It is a happy number.

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., 13965169 + 6692569 = 3737^2 + 2587^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5164433 + ... + 5164436.

Almost surely, 2^20657738 is an apocalyptic number.

20657738 is a deficient number, since it is larger than the sum of its proper divisors (10328872).

20657738 is a wasteful number, since it uses less digits than its factorization.

20657738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10328871.

The product of its (nonzero) digits is 70560, while the sum is 38.

The square root of 20657738 is about 4545.0784371670. The cubic root of 20657738 is about 274.3853511972.

The spelling of 20657738 in words is "twenty million, six hundred fifty-seven thousand, seven hundred thirty-eight".