19650663990 has 48 divisors (see below), whose sum is σ = 52984019088. Its totient is φ = 5240176416.

The previous prime is 19650663979. The next prime is 19650664009. The reversal of 19650663990 is 9936605691.

It is a happy number.

19650663990 is a `hidden beast` number, since 19 + 6 + 506 + 6 + 39 + 90 = 666.

It is a super-2 number, since 2×19650663990² (a number of 21 digits) contains 22 as substring.

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 23 ways as a sum of consecutive naturals, for example, 4040917 + ... + 4045776.

It is an arithmetic number, because the mean of its divisors is an integer number (1103833731).

Almost surely, 2^19650663990 is an apocalyptic number.

19650663990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

19650663990 is an abundant number, since it is smaller than the sum of its proper divisors (33333355098).

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

19650663990 is an equidigital number, since it uses as much as digits as its factorization.

19650663990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8086715 (or 8086703 counting only the distinct ones).

The product of its (nonzero) digits is 2361960, while the sum is 54.

The spelling of 19650663990 in words is "nineteen billion, six hundred fifty million, six hundred sixty-three thousand, nine hundred ninety".