19407971540 has 24 divisors (see below), whose sum is σ = 40877694312. Its totient is φ = 7740149760.

The previous prime is 19407971537. The next prime is 19407971551. The reversal of 19407971540 is 4517970491.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 3724416784 + 15683554756 = 61028^2 + 125234^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1433021 + ... + 1446500.

It is an arithmetic number, because the mean of its divisors is an integer number (1703237263).

Almost surely, 2^19407971540 is an apocalyptic number.

19407971540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19407971540 is an abundant number, since it is smaller than the sum of its proper divisors (21469722772).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19407971540 is a wasteful number, since it uses less digits than its factorization.

19407971540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2879867 (or 2879865 counting only the distinct ones).

The product of its (nonzero) digits is 317520, while the sum is 47.

The spelling of 19407971540 in words is "nineteen billion, four hundred seven million, nine hundred seventy-one thousand, five hundred forty".