19695491712 has 512 divisors, whose sum is σ = 67179974400. Its totient is φ = 5626920960.

The previous prime is 19695491657. The next prime is 19695491737. The reversal of 19695491712 is 21719459691.

It is a happy number.

19695491712 is a `hidden beast` number, since 1 + 96 + 9 + 549 + 1 + 7 + 1 + 2 = 666.

It is a super-4 number, since 4×19695491712⁴ (a number of 42 digits) contains 4444 as substring.

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

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 81723912 + ... + 81724152.

Almost surely, 2^19695491712 is an apocalyptic number.

19695491712 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 19695491712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33589987200).

19695491712 is an abundant number, since it is smaller than the sum of its proper divisors (47484482688).

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

19695491712 is a wasteful number, since it uses less digits than its factorization.

19695491712 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 401 (or 383 counting only the distinct ones).

The product of its digits is 1224720, while the sum is 54.

The spelling of 19695491712 in words is "nineteen billion, six hundred ninety-five million, four hundred ninety-one thousand, seven hundred twelve".