20657145706 has 8 divisors (see below), whose sum is σ = 32808407940. Its totient is φ = 9721009728.

The previous prime is 20657145683. The next prime is 20657145731. The reversal of 20657145706 is 60754175602.

It can be written as a sum of positive squares in 2 ways, for example, as 19602520081 + 1054625625 = 140009^2 + 32475^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 303781521 + ... + 303781588.

Almost surely, 2^20657145706 is an apocalyptic number.

20657145706 is a deficient number, since it is larger than the sum of its proper divisors (12151262234).

20657145706 is a wasteful number, since it uses less digits than its factorization.

20657145706 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 607563128.

The product of its (nonzero) digits is 352800, while the sum is 43.

The spelling of 20657145706 in words is "twenty billion, six hundred fifty-seven million, one hundred forty-five thousand, seven hundred six".