20101521440 has 192 divisors, whose sum is σ = 63763096320. Its totient is φ = 5783408640.

The previous prime is 20101521403. The next prime is 20101521457. The reversal of 20101521440 is 4412510102.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 97406 + ... + 222914.

It is an arithmetic number, because the mean of its divisors is an integer number (332099460).

Almost surely, 2^20101521440 is an apocalyptic number.

20101521440 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 20101521440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31881548160).

20101521440 is an abundant number, since it is smaller than the sum of its proper divisors (43661574880).

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

20101521440 is a wasteful number, since it uses less digits than its factorization.

20101521440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125555 (or 125547 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 20.

The spelling of 20101521440 in words is "twenty billion, one hundred one million, five hundred twenty-one thousand, four hundred forty".