19930667957 has 4 divisors (see below), whose sum is σ = 19931446860. Its totient is φ = 19929889056.

The previous prime is 19930667941. The next prime is 19930667959. The reversal of 19930667957 is 75976603991.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8480383921 + 11450284036 = 92089^2 + 107006^2 .

It is a cyclic number.

It is not a de Polignac number, because 19930667957 - 2⁴ = 19930667941 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 19930667957.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19930667959) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 349718 + ... + 402695.

It is an arithmetic number, because the mean of its divisors is an integer number (4982861715).

Almost surely, 2^19930667957 is an apocalyptic number.

It is an amenable number.

19930667957 is a deficient number, since it is larger than the sum of its proper divisors (778903).

19930667957 is an equidigital number, since it uses as much as digits as its factorization.

19930667957 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 778902.

The product of its (nonzero) digits is 19289340, while the sum is 62.

The spelling of 19930667957 in words is "nineteen billion, nine hundred thirty million, six hundred sixty-seven thousand, nine hundred fifty-seven".