19440638620 has 24 divisors (see below), whose sum is σ = 43965752544. Its totient is φ = 7178081856.

The previous prime is 19440638593. The next prime is 19440638653. The reversal of 19440638620 is 2683604491.

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 7 ways as a sum of consecutive naturals, for example, 37385584 + ... + 37386103.

It is an arithmetic number, because the mean of its divisors is an integer number (1831906356).

Almost surely, 2^19440638620 is an apocalyptic number.

19440638620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19440638620 is an abundant number, since it is smaller than the sum of its proper divisors (24525113924).

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

19440638620 is a wasteful number, since it uses less digits than its factorization.

19440638620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74771709 (or 74771707 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 43.

The spelling of 19440638620 in words is "nineteen billion, four hundred forty million, six hundred thirty-eight thousand, six hundred twenty".