19445020920 has 512 divisors, whose sum is σ = 74430316800. Its totient is φ = 4473225216.

The previous prime is 19445020879. The next prime is 19445020951. The reversal of 19445020920 is 2902054491.

19445020920 is a `hidden beast` number, since 1 + 9 + 445 + 0 + 209 + 2 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 61340602 + ... + 61340918.

Almost surely, 2^19445020920 is an apocalyptic number.

19445020920 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 19445020920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37215158400).

19445020920 is an abundant number, since it is smaller than the sum of its proper divisors (54985295880).

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

19445020920 is a wasteful number, since it uses less digits than its factorization.

19445020920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 624 (or 614 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The spelling of 19445020920 in words is "nineteen billion, four hundred forty-five million, twenty thousand, nine hundred twenty".