20853562464 has 144 divisors (see below), whose sum is σ = 67827352320. Its totient is φ = 5953478400.

The previous prime is 20853562441. The next prime is 20853562481. The reversal of 20853562464 is 46426535802.

20853562464 is a `hidden beast` number, since 2 + 0 + 85 + 3 + 562 + 4 + 6 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

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, 3179989 + ... + 3186539.

It is an arithmetic number, because the mean of its divisors is an integer number (471023280).

Almost surely, 2^20853562464 is an apocalyptic number.

20853562464 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 20853562464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33913676160).

20853562464 is an abundant number, since it is smaller than the sum of its proper divisors (46973789856).

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

20853562464 is a wasteful number, since it uses less digits than its factorization.

20853562464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8153 (or 8142 counting only the distinct ones).

The product of its (nonzero) digits is 1382400, while the sum is 45.

The spelling of 20853562464 in words is "twenty billion, eight hundred fifty-three million, five hundred sixty-two thousand, four hundred sixty-four".