19557372973 has 2 divisors, whose sum is σ = 19557372974. Its totient is φ = 19557372972.

The previous prime is 19557372953. The next prime is 19557373051. The reversal of 19557372973 is 37927375591.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17732118244 + 1825254729 = 133162^2 + 42723^2 .

It is a cyclic number.

It is not a de Polignac number, because 19557372973 - 2⁵ = 19557372941 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19557372953) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9778686486 + 9778686487.

It is an arithmetic number, because the mean of its divisors is an integer number (9778686487).

Almost surely, 2^19557372973 is an apocalyptic number.

It is an amenable number.

19557372973 is a deficient number, since it is larger than the sum of its proper divisors (1).

19557372973 is an equidigital number, since it uses as much as digits as its factorization.

19557372973 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12502350, while the sum is 58.

The spelling of 19557372973 in words is "nineteen billion, five hundred fifty-seven million, three hundred seventy-two thousand, nine hundred seventy-three".