20493471956 has 6 divisors (see below), whose sum is σ = 35863575930. Its totient is φ = 10246735976.

The previous prime is 20493471949. The next prime is 20493472063. The reversal of 20493471956 is 65917439402.

It can be written as a sum of positive squares in only one way, i.e., 11736255556 + 8757216400 = 108334^2 + 93580^2 .

It is a super-2 number, since 2×20493471956² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

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, 2561683991 + ... + 2561683998.

It is an arithmetic number, because the mean of its divisors is an integer number (5977262655).

Almost surely, 2^20493471956 is an apocalyptic number.

It is an amenable number.

20493471956 is a deficient number, since it is larger than the sum of its proper divisors (15370103974).

20493471956 is a wasteful number, since it uses less digits than its factorization.

20493471956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5123367993 (or 5123367991 counting only the distinct ones).

The product of its (nonzero) digits is 1632960, while the sum is 50.

The spelling of 20493471956 in words is "twenty billion, four hundred ninety-three million, four hundred seventy-one thousand, nine hundred fifty-six".