28391908380 has 48 divisors (see below), whose sum is σ = 86724376704. Its totient is φ = 6882886720.

The previous prime is 28391908351. The next prime is 28391908393. The reversal of 28391908380 is 8380919382.

It is a super-2 number, since 2×28391908380² (a number of 22 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 15 ways as a sum of consecutive naturals, for example, 21508362 + ... + 21509681.

It is an arithmetic number, because the mean of its divisors is an integer number (1806757848).

Almost surely, 2^28391908380 is an apocalyptic number.

28391908380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28391908380 is an abundant number, since it is smaller than the sum of its proper divisors (58332468324).

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

28391908380 is a wasteful number, since it uses less digits than its factorization.

28391908380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43018066 (or 43018064 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 51.

The spelling of 28391908380 in words is "twenty-eight billion, three hundred ninety-one million, nine hundred eight thousand, three hundred eighty".