20151553328640 has 480 divisors, whose sum is σ = 74056088785536. Its totient is φ = 5046675701760.

The previous prime is 20151553328551. The next prime is 20151553328663. The reversal of 20151553328640 is 4682335515102.

It is a happy number.

20151553328640 is a `hidden beast` number, since 2 + 0 + 1 + 5 + 1 + 553 + 32 + 8 + 64 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (480).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 181292280 + ... + 181403400.

Almost surely, 2^{20151553328640} is an apocalyptic number.

20151553328640 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 20151553328640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37028044392768).

20151553328640 is an abundant number, since it is smaller than the sum of its proper divisors (53904535456896).

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

20151553328640 is a wasteful number, since it uses less digits than its factorization.

20151553328640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111630 (or 111611 counting only the distinct ones).

The product of its (nonzero) digits is 864000, while the sum is 45.

The spelling of 20151553328640 in words is "twenty trillion, one hundred fifty-one billion, five hundred fifty-three million, three hundred twenty-eight thousand, six hundred forty".