20640294475 has 6 divisors (see below), whose sum is σ = 25593965180. Its totient is φ = 16512235560.

The previous prime is 20640294457. The next prime is 20640294509. The reversal of 20640294475 is 57449204602.

It is not a de Polignac number, because 20640294475 - 2¹⁹ = 20639770187 is a prime.

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 5 ways as a sum of consecutive naturals, for example, 412805865 + ... + 412805914.

Almost surely, 2^20640294475 is an apocalyptic number.

20640294475 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20640294475 is a deficient number, since it is larger than the sum of its proper divisors (4953670705).

20640294475 is an equidigital number, since it uses as much as digits as its factorization.

20640294475 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 825611789 (or 825611784 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 43.

The spelling of 20640294475 in words is "twenty billion, six hundred forty million, two hundred ninety-four thousand, four hundred seventy-five".