19910478672 has 160 divisors (see below), whose sum is σ = 65489141760. Its totient is φ = 5673525120.

The previous prime is 19910478649. The next prime is 19910478713. The reversal of 19910478672 is 27687401991.

19910478672 is a `hidden beast` number, since 1 + 99 + 10 + 478 + 6 + 72 = 666.

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 31 ways as a sum of consecutive naturals, for example, 1149597 + ... + 1166787.

It is an arithmetic number, because the mean of its divisors is an integer number (409307136).

Almost surely, 2^19910478672 is an apocalyptic number.

19910478672 is a gapful number since it is divisible by the number (12) 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 19910478672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32744570880).

19910478672 is an abundant number, since it is smaller than the sum of its proper divisors (45578663088).

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

19910478672 is a wasteful number, since it uses less digits than its factorization.

19910478672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17598 (or 17586 counting only the distinct ones).

The product of its (nonzero) digits is 1524096, while the sum is 54.

The spelling of 19910478672 in words is "nineteen billion, nine hundred ten million, four hundred seventy-eight thousand, six hundred seventy-two".