20915228125440 has 2304 divisors, whose sum is σ = 86407630848000. Its totient is φ = 4743335116800.

The previous prime is 20915228125427. The next prime is 20915228125469. The reversal of 20915228125440 is 4452182251902.

20915228125440 is a `hidden beast` number, since 2 + 0 + 9 + 1 + 5 + 22 + 81 + 2 + 544 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (2304).

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 255 ways as a sum of consecutive naturals, for example, 75506238582 + ... + 75506238858.

It is an arithmetic number, because the mean of its divisors is an integer number (37503312000).

Almost surely, 2^{20915228125440} is an apocalyptic number.

20915228125440 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 20915228125440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43203815424000).

20915228125440 is an abundant number, since it is smaller than the sum of its proper divisors (65492402722560).

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

20915228125440 is a wasteful number, since it uses less digits than its factorization.

20915228125440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 541 (or 521 counting only the distinct ones).

The product of its (nonzero) digits is 460800, while the sum is 45.

The spelling of 20915228125440 in words is "twenty trillion, nine hundred fifteen billion, two hundred twenty-eight million, one hundred twenty-five thousand, four hundred forty".