20415511072 has 144 divisors (see below), whose sum is σ = 47780409600. Its totient is φ = 8546785280.

The previous prime is 20415511057. The next prime is 20415511117. The reversal of 20415511072 is 27011551402.

It is a self number, because there is not a number n which added to its sum of digits gives 20415511072.

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, 3090429 + ... + 3097027.

It is an arithmetic number, because the mean of its divisors is an integer number (331808400).

Almost surely, 2^20415511072 is an apocalyptic number.

20415511072 is a gapful number since it is divisible by the number (22) 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 20415511072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23890204800).

20415511072 is an abundant number, since it is smaller than the sum of its proper divisors (27364898528).

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

20415511072 is a wasteful number, since it uses less digits than its factorization.

20415511072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6695 (or 6676 counting only the distinct ones).

The product of its (nonzero) digits is 2800, while the sum is 28.

The spelling of 20415511072 in words is "twenty billion, four hundred fifteen million, five hundred eleven thousand, seventy-two".