28157772500 has 240 divisors, whose sum is σ = 73329527040. Its totient is φ = 9322560000.

The previous prime is 28157772481. The next prime is 28157772547. The reversal of 28157772500 is 527775182.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 28242002 + ... + 28242998.

It is an arithmetic number, because the mean of its divisors is an integer number (305539696).

Almost surely, 2^28157772500 is an apocalyptic number.

28157772500 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 28157772500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36664763520).

28157772500 is an abundant number, since it is smaller than the sum of its proper divisors (45171754540).

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

28157772500 is a wasteful number, since it uses less digits than its factorization.

28157772500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1124 (or 1107 counting only the distinct ones).

The product of its (nonzero) digits is 274400, while the sum is 44.

The spelling of 28157772500 in words is "twenty-eight billion, one hundred fifty-seven million, seven hundred seventy-two thousand, five hundred".