20501603057 has 4 divisors (see below), whose sum is σ = 22078649460. Its totient is φ = 18924556656.

The previous prime is 20501602991. The next prime is 20501603071. The reversal of 20501603057 is 75030610502.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1057810576 + 19443792481 = 32524^2 + 139441^2 .

It is a cyclic number.

It is not a de Polignac number, because 20501603057 - 2¹⁴ = 20501586673 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20501603657) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 788523182 + ... + 788523207.

It is an arithmetic number, because the mean of its divisors is an integer number (5519662365).

Almost surely, 2^20501603057 is an apocalyptic number.

It is an amenable number.

20501603057 is a deficient number, since it is larger than the sum of its proper divisors (1577046403).

20501603057 is a wasteful number, since it uses less digits than its factorization.

20501603057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1577046402.

The product of its (nonzero) digits is 6300, while the sum is 29.

The spelling of 20501603057 in words is "twenty billion, five hundred one million, six hundred three thousand, fifty-seven".