28981929780 has 54 divisors (see below), whose sum is σ = 87918782406. Its totient is φ = 7727905536.

The previous prime is 28981929773. The next prime is 28981929787. The reversal of 28981929780 is 8792918982.

28981929780 is a `hidden beast` number, since 289 + 8 + 192 + 97 + 80 = 666.

It is an interprime number because it is at equal distance from previous prime (28981929773) and next prime (28981929787).

It can be written as a sum of positive squares in 3 ways, for example, as 436475664 + 28545454116 = 20892^2 + 168954^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28981929787) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 2277676 + ... + 2290364.

Almost surely, 2^28981929780 is an apocalyptic number.

28981929780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28981929780 is an abundant number, since it is smaller than the sum of its proper divisors (58936852626).

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

28981929780 is an equidigital number, since it uses as much as digits as its factorization.

28981929780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25393 (or 12699 counting only the distinct ones).

The product of its (nonzero) digits is 10450944, while the sum is 63.

The spelling of 28981929780 in words is "twenty-eight billion, nine hundred eighty-one million, nine hundred twenty-nine thousand, seven hundred eighty".