28977917 has 4 divisors (see below), whose sum is σ = 29259360. Its totient is φ = 28696476.

The previous prime is 28977899. The next prime is 28977929. The reversal of 28977917 is 71977982.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 71977982 = 2 ⋅35988991.

It is a cyclic number.

It is not a de Polignac number, because 28977917 - 2⁸ = 28977661 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 (28977937) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 140567 + ... + 140772.

It is an arithmetic number, because the mean of its divisors is an integer number (7314840).

Almost surely, 2^28977917 is an apocalyptic number.

It is an amenable number.

28977917 is a deficient number, since it is larger than the sum of its proper divisors (281443).

28977917 is a wasteful number, since it uses less digits than its factorization.

28977917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281442.

The product of its digits is 444528, while the sum is 50.

The square root of 28977917 is about 5383.1140615818. The cubic root of 28977917 is about 307.1536788894.

The spelling of 28977917 in words is "twenty-eight million, nine hundred seventy-seven thousand, nine hundred seventeen".