28780877 has 4 divisors (see below), whose sum is σ = 30295680. Its totient is φ = 27266076.

The previous prime is 28780861. The next prime is 28780891. The reversal of 28780877 is 77808782.

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.

It is a cyclic number.

It is not a de Polignac number, because 28780877 - 2⁴ = 28780861 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 (28780897) 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, 757373 + ... + 757410.

It is an arithmetic number, because the mean of its divisors is an integer number (7573920).

Almost surely, 2^28780877 is an apocalyptic number.

It is an amenable number.

28780877 is a deficient number, since it is larger than the sum of its proper divisors (1514803).

28780877 is a wasteful number, since it uses less digits than its factorization.

28780877 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1514802.

The product of its (nonzero) digits is 351232, while the sum is 47.

The square root of 28780877 is about 5364.7811698149. The cubic root of 28780877 is about 306.4559147172.

The spelling of 28780877 in words is "twenty-eight million, seven hundred eighty thousand, eight hundred seventy-seven".