19999073961 has 8 divisors (see below), whose sum is σ = 29628257760. Its totient is φ = 13332715956.

The previous prime is 19999073957. The next prime is 19999074019. The reversal of 19999073961 is 16937099991.

It is not a de Polignac number, because 19999073961 - 2² = 19999073957 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19999073161) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 370353195 + ... + 370353248.

It is an arithmetic number, because the mean of its divisors is an integer number (3703532220).

Almost surely, 2^19999073961 is an apocalyptic number.

It is an amenable number.

19999073961 is a deficient number, since it is larger than the sum of its proper divisors (9629183799).

19999073961 is an equidigital number, since it uses as much as digits as its factorization.

19999073961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 740706452 (or 740706446 counting only the distinct ones).

The product of its (nonzero) digits is 7440174, while the sum is 63.

The spelling of 19999073961 in words is "nineteen billion, nine hundred ninety-nine million, seventy-three thousand, nine hundred sixty-one".