28742238 has 24 divisors (see below), whose sum is σ = 71171568. Its totient is φ = 8212032.

The previous prime is 28742227. The next prime is 28742243. The reversal of 28742238 is 83224782.

It is a super-2 number, since 2×28742238² = 1652232490497288, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 113931 + ... + 114182.

It is an arithmetic number, because the mean of its divisors is an integer number (2965482).

Almost surely, 2^28742238 is an apocalyptic number.

28742238 is an abundant number, since it is smaller than the sum of its proper divisors (42429330).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28742238 is a wasteful number, since it uses less digits than its factorization.

28742238 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 228128 (or 228125 counting only the distinct ones).

The product of its digits is 43008, while the sum is 36.

The square root of 28742238 is about 5361.1787882890. The cubic root of 28742238 is about 306.3187118903.

The spelling of 28742238 in words is "twenty-eight million, seven hundred forty-two thousand, two hundred thirty-eight".