20615515000 has 80 divisors (see below), whose sum is σ = 48845926800. Its totient is φ = 8153376000.

The previous prime is 20615514991. The next prime is 20615515027. The reversal of 20615515000 is 51551602.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 421837 + ... + 468163.

It is an arithmetic number, because the mean of its divisors is an integer number (610574085).

Almost surely, 2^20615515000 is an apocalyptic number.

20615515000 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 20615515000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24422963400).

20615515000 is an abundant number, since it is smaller than the sum of its proper divisors (28230411800).

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

20615515000 is an equidigital number, since it uses as much as digits as its factorization.

20615515000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46442 (or 46423 counting only the distinct ones).

The product of its (nonzero) digits is 1500, while the sum is 25.

The spelling of 20615515000 in words is "twenty billion, six hundred fifteen million, five hundred fifteen thousand".