19789450840 has 16 divisors (see below), whose sum is σ = 44526264480. Its totient is φ = 7915780320.

The previous prime is 19789450819. The next prime is 19789450859. The reversal of 19789450840 is 4805498791.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 247368096 + ... + 247368175.

It is an arithmetic number, because the mean of its divisors is an integer number (2782891530).

Almost surely, 2^19789450840 is an apocalyptic number.

19789450840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19789450840 is an abundant number, since it is smaller than the sum of its proper divisors (24736813640).

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

19789450840 is a wasteful number, since it uses less digits than its factorization.

19789450840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 494736282 (or 494736278 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 55.

The spelling of 19789450840 in words is "nineteen billion, seven hundred eighty-nine million, four hundred fifty thousand, eight hundred forty".