28997031 has 8 divisors (see below), whose sum is σ = 44185984. Its totient is φ = 16569720.

The previous prime is 28997027. The next prime is 28997041. The reversal of 28997031 is 13079982.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28997031 - 2² = 28997027 is a prime.

It is a super-2 number, since 2×28997031² = 1681655613629922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28997041) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 690385 + ... + 690426.

It is an arithmetic number, because the mean of its divisors is an integer number (5523248).

Almost surely, 2^28997031 is an apocalyptic number.

28997031 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

28997031 is a deficient number, since it is larger than the sum of its proper divisors (15188953).

28997031 is a wasteful number, since it uses less digits than its factorization.

28997031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1380821.

The product of its (nonzero) digits is 27216, while the sum is 39.

The square root of 28997031 is about 5384.8891353490. The cubic root of 28997031 is about 307.2211974882.

The spelling of 28997031 in words is "twenty-eight million, nine hundred ninety-seven thousand, thirty-one".