20198762640 has 480 divisors, whose sum is σ = 81010814976. Its totient is φ = 4581619200.

The previous prime is 20198762539. The next prime is 20198762671. The reversal of 20198762640 is 4626789102.

It is a happy number.

20198762640 is a `hidden beast` number, since 2 + 0 + 19 + 8 + 7 + 626 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 20547589 + ... + 20548571.

Almost surely, 2^20198762640 is an apocalyptic number.

20198762640 is a gapful number since it is divisible by the number (20) 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 20198762640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40505407488).

20198762640 is an abundant number, since it is smaller than the sum of its proper divisors (60812052336).

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

20198762640 is a wasteful number, since it uses less digits than its factorization.

20198762640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1169 (or 1151 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 45.

The spelling of 20198762640 in words is "twenty billion, one hundred ninety-eight million, seven hundred sixty-two thousand, six hundred forty".