20494745691 has 32 divisors (see below), whose sum is σ = 31327574016. Its totient is φ = 11674800000.

The previous prime is 20494745683. The next prime is 20494745707. The reversal of 20494745691 is 19654749402.

It is not a de Polignac number, because 20494745691 - 2³ = 20494745683 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20494745681) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 14839821 + ... + 14841201.

It is an arithmetic number, because the mean of its divisors is an integer number (978986688).

Almost surely, 2^20494745691 is an apocalyptic number.

20494745691 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

20494745691 is a deficient number, since it is larger than the sum of its proper divisors (10832828325).

20494745691 is a wasteful number, since it uses less digits than its factorization.

20494745691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3083.

The product of its (nonzero) digits is 2177280, while the sum is 51.

The spelling of 20494745691 in words is "twenty billion, four hundred ninety-four million, seven hundred forty-five thousand, six hundred ninety-one".