28783557 has 24 divisors (see below), whose sum is σ = 47331648. Its totient is φ = 16684800.

The previous prime is 28783553. The next prime is 28783561. The reversal of 28783557 is 75538782.

28783557 is a `hidden beast` number, since 28 + 78 + 3 + 557 = 666.

It is an interprime number because it is at equal distance from previous prime (28783553) and next prime (28783561).

It is not a de Polignac number, because 28783557 - 2² = 28783553 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28783553) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4044 + ... + 8597.

It is an arithmetic number, because the mean of its divisors is an integer number (1972152).

Almost surely, 2^28783557 is an apocalyptic number.

It is an amenable number.

28783557 is a deficient number, since it is larger than the sum of its proper divisors (18548091).

28783557 is a wasteful number, since it uses less digits than its factorization.

28783557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12681 (or 12678 counting only the distinct ones).

The product of its digits is 470400, while the sum is 45.

The square root of 28783557 is about 5365.0309411969. The cubic root of 28783557 is about 306.4654265464.

The spelling of 28783557 in words is "twenty-eight million, seven hundred eighty-three thousand, five hundred fifty-seven".