20453661864 has 192 divisors, whose sum is σ = 60909488640. Its totient is φ = 6418932480.

The previous prime is 20453661847. The next prime is 20453661871. The reversal of 20453661864 is 46816635402.

20453661864 is a `hidden beast` number, since 20 + 4 + 5 + 3 + 6 + 618 + 6 + 4 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2225182 + ... + 2234354.

It is an arithmetic number, because the mean of its divisors is an integer number (317236920).

Almost surely, 2^20453661864 is an apocalyptic number.

20453661864 is a gapful number since it is divisible by the number (24) 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 20453661864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30454744320).

20453661864 is an abundant number, since it is smaller than the sum of its proper divisors (40455826776).

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

20453661864 is a wasteful number, since it uses less digits than its factorization.

20453661864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9262 (or 9246 counting only the distinct ones).

The product of its (nonzero) digits is 829440, while the sum is 45.

The spelling of 20453661864 in words is "twenty billion, four hundred fifty-three million, six hundred sixty-one thousand, eight hundred sixty-four".