42906991 has 8 divisors (see below), whose sum is σ = 44509520. Its totient is φ = 41332032.

The previous prime is 42906977. The next prime is 42907003. The reversal of 42906991 is 19960924.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42906991 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 (42906931) 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, 3696 + ... + 9973.

It is an arithmetic number, because the mean of its divisors is an integer number (5563690).

Almost surely, 2^42906991 is an apocalyptic number.

42906991 is a deficient number, since it is larger than the sum of its proper divisors (1602529).

42906991 is a wasteful number, since it uses less digits than its factorization.

42906991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13785.

The product of its (nonzero) digits is 34992, while the sum is 40.

The square root of 42906991 is about 6550.3428154563. The cubic root of 42906991 is about 350.0870286984.

The spelling of 42906991 in words is "forty-two million, nine hundred six thousand, nine hundred ninety-one".