28399472640 has 1664 divisors, whose sum is σ = 135878860800. Its totient is φ = 5449973760.

The previous prime is 28399472623. The next prime is 28399472657. The reversal of 28399472640 is 4627499382.

28399472640 is a `hidden beast` number, since 2 + 83 + 99 + 472 + 6 + 4 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (28399472623) and next prime (28399472657).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 979292146 + ... + 979292174.

Almost surely, 2^28399472640 is an apocalyptic number.

28399472640 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 28399472640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (67939430400).

28399472640 is an abundant number, since it is smaller than the sum of its proper divisors (107479388160).

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

28399472640 is a wasteful number, since it uses less digits than its factorization.

28399472640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108 (or 80 counting only the distinct ones).

The product of its (nonzero) digits is 5225472, while the sum is 54.

The spelling of 28399472640 in words is "twenty-eight billion, three hundred ninety-nine million, four hundred seventy-two thousand, six hundred forty".