28909400331 has 32 divisors (see below), whose sum is σ = 45489934336. Its totient is φ = 15980976000.

The previous prime is 28909400287. The next prime is 28909400341. The reversal of 28909400331 is 13300490982.

It is not a de Polignac number, because 28909400331 - 2⁷ = 28909400203 is a prime.

It is a super-2 number, since 2×28909400331² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28909400331.

It is not an unprimeable number, because it can be changed into a prime (28909400341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2298921 + ... + 2311461.

It is an arithmetic number, because the mean of its divisors is an integer number (1421560448).

Almost surely, 2^28909400331 is an apocalyptic number.

28909400331 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

28909400331 is a deficient number, since it is larger than the sum of its proper divisors (16580534005).

28909400331 is a wasteful number, since it uses less digits than its factorization.

28909400331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16123.

The product of its (nonzero) digits is 46656, while the sum is 39.

The spelling of 28909400331 in words is "twenty-eight billion, nine hundred nine million, four hundred thousand, three hundred thirty-one".