19639895040 has 880 divisors, whose sum is σ = 77040564480. Its totient is φ = 4768727040.

The previous prime is 19639894979. The next prime is 19639895081. The reversal of 19639895040 is 4059893691.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 276618205 + ... + 276618275.

It is an arithmetic number, because the mean of its divisors is an integer number (87546096).

Almost surely, 2^19639895040 is an apocalyptic number.

19639895040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19639895040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38520282240).

19639895040 is an abundant number, since it is smaller than the sum of its proper divisors (57400669440).

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

19639895040 is a wasteful number, since it uses less digits than its factorization.

19639895040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160 (or 133 counting only the distinct ones).

The product of its (nonzero) digits is 2099520, while the sum is 54.

The spelling of 19639895040 in words is "nineteen billion, six hundred thirty-nine million, eight hundred ninety-five thousand, forty".