20494672691 has 2 divisors, whose sum is σ = 20494672692. Its totient is φ = 20494672690.

The previous prime is 20494672613. The next prime is 20494672703. The reversal of 20494672691 is 19627649402.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20494672691 is a prime.

It is a super-2 number, since 2×20494672691² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20494672591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10247336345 + 10247336346.

It is an arithmetic number, because the mean of its divisors is an integer number (10247336346).

Almost surely, 2^20494672691 is an apocalyptic number.

20494672691 is a deficient number, since it is larger than the sum of its proper divisors (1).

20494672691 is an equidigital number, since it uses as much as digits as its factorization.

20494672691 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1306368, while the sum is 50.

The spelling of 20494672691 in words is "twenty billion, four hundred ninety-four million, six hundred seventy-two thousand, six hundred ninety-one".