18951443671 has 2 divisors, whose sum is σ = 18951443672. Its totient is φ = 18951443670.

The previous prime is 18951443663. The next prime is 18951443681. The reversal of 18951443671 is 17634415981.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18951443671 - 2³ = 18951443663 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18951443681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9475721835 + 9475721836.

It is an arithmetic number, because the mean of its divisors is an integer number (9475721836).

Almost surely, 2^18951443671 is an apocalyptic number.

18951443671 is a deficient number, since it is larger than the sum of its proper divisors (1).

18951443671 is an equidigital number, since it uses as much as digits as its factorization.

18951443671 is an evil number, because the sum of its binary digits is even.

The product of its digits is 725760, while the sum is 49.

The spelling of 18951443671 in words is "eighteen billion, nine hundred fifty-one million, four hundred forty-three thousand, six hundred seventy-one".