42890591 has 4 divisors (see below), whose sum is σ = 42915432. Its totient is φ = 42865752.

The previous prime is 42890569. The next prime is 42890593. The reversal of 42890591 is 19509824.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42890591 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 (42890593) 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, 9620 + ... + 13353.

It is an arithmetic number, because the mean of its divisors is an integer number (10728858).

Almost surely, 2^42890591 is an apocalyptic number.

42890591 is a deficient number, since it is larger than the sum of its proper divisors (24841).

42890591 is a wasteful number, since it uses less digits than its factorization.

42890591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24840.

The product of its (nonzero) digits is 25920, while the sum is 38.

The square root of 42890591 is about 6549.0908529352. The cubic root of 42890591 is about 350.0424193484.

It can be divided in two parts, 428 and 90591, that added together give a palindrome (91019).

The spelling of 42890591 in words is "forty-two million, eight hundred ninety thousand, five hundred ninety-one".