28870720421 has 16 divisors (see below), whose sum is σ = 29411289600. Its totient is φ = 28335979008.

The previous prime is 28870720397. The next prime is 28870720427. The reversal of 28870720421 is 12402707882.

It is a cyclic number.

It is not a de Polignac number, because 28870720421 - 2¹⁸ = 28870458277 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28870720427) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 7364900 + ... + 7368818.

It is an arithmetic number, because the mean of its divisors is an integer number (1838205600).

Almost surely, 2^28870720421 is an apocalyptic number.

It is an amenable number.

28870720421 is a deficient number, since it is larger than the sum of its proper divisors (540569179).

28870720421 is a wasteful number, since it uses less digits than its factorization.

28870720421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4628.

The product of its (nonzero) digits is 100352, while the sum is 41.

The spelling of 28870720421 in words is "twenty-eight billion, eight hundred seventy million, seven hundred twenty thousand, four hundred twenty-one".