42991128 has 32 divisors (see below), whose sum is σ = 119420400. Its totient is φ = 14330304.

The previous prime is 42991127. The next prime is 42991133. The reversal of 42991128 is 82119924.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 42991092 and 42991101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42991121) 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, 99301 + ... + 99732.

Almost surely, 2^42991128 is an apocalyptic number.

It is an amenable number.

42991128 is an abundant number, since it is smaller than the sum of its proper divisors (76429272).

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

42991128 is a wasteful number, since it uses less digits than its factorization.

42991128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199048 (or 199038 counting only the distinct ones).

The product of its digits is 10368, while the sum is 36.

The square root of 42991128 is about 6556.7620057464. The cubic root of 42991128 is about 350.3157096933.

The spelling of 42991128 in words is "forty-two million, nine hundred ninety-one thousand, one hundred twenty-eight".