42591816 has 24 divisors (see below), whose sum is σ = 115353030. Its totient is φ = 14197248.

The previous prime is 42591811. The next prime is 42591841. The reversal of 42591816 is 61819524.

It can be written as a sum of positive squares in only one way, i.e., 37088100 + 5503716 = 6090^2 + 2346^2 .

It is a tau number, because it is divible by the number of its divisors (24).

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

It is not an unprimeable number, because it can be changed into a prime (42591811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 295705 + ... + 295848.

Almost surely, 2^42591816 is an apocalyptic number.

It is an amenable number.

42591816 is an abundant number, since it is smaller than the sum of its proper divisors (72761214).

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

42591816 is a wasteful number, since it uses less digits than its factorization.

42591816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 591565 (or 591558 counting only the distinct ones).

The product of its digits is 17280, while the sum is 36.

The square root of 42591816 is about 6526.2405717227. The cubic root of 42591816 is about 349.2277285366.

The spelling of 42591816 in words is "forty-two million, five hundred ninety-one thousand, eight hundred sixteen".