28399931951040 has 560 divisors, whose sum is σ = 108835822041408. Its totient is φ = 6988103663616.

The previous prime is 28399931951011. The next prime is 28399931951099. The reversal of 28399931951040 is 4015913999382.

28399931951040 is a `hidden beast` number, since 2 + 8 + 399 + 9 + 3 + 195 + 10 + 40 = 666.

It is a super-2 number, since 2×28399931951040² (a number of 28 digits) contains 22 as substring.

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, 978180364 + ... + 978209396.

Almost surely, 2^{28399931951040} is an apocalyptic number.

28399931951040 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 28399931951040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (54417911020704).

28399931951040 is an abundant number, since it is smaller than the sum of its proper divisors (80435890090368).

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

28399931951040 is a wasteful number, since it uses less digits than its factorization.

28399931951040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31978 (or 31959 counting only the distinct ones).

The product of its (nonzero) digits is 18895680, while the sum is 63.

The spelling of 28399931951040 in words is "twenty-eight trillion, three hundred ninety-nine billion, nine hundred thirty-one million, nine hundred fifty-one thousand, forty".