28251969720 has 128 divisors (see below), whose sum is σ = 91574461440. Its totient is φ = 6931560960.

The previous prime is 28251969653. The next prime is 28251969731. The reversal of 28251969720 is 2796915282.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 449425 + ... + 508415.

It is an arithmetic number, because the mean of its divisors is an integer number (715425480).

Almost surely, 2^28251969720 is an apocalyptic number.

28251969720 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 28251969720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45787230720).

28251969720 is an abundant number, since it is smaller than the sum of its proper divisors (63322491720).

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

28251969720 is a wasteful number, since it uses less digits than its factorization.

28251969720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59325 (or 59321 counting only the distinct ones).

The product of its (nonzero) digits is 1088640, while the sum is 51.

The spelling of 28251969720 in words is "twenty-eight billion, two hundred fifty-one million, nine hundred sixty-nine thousand, seven hundred twenty".