42390997 has 4 divisors (see below), whose sum is σ = 46244736. Its totient is φ = 38537260.

The previous prime is 42390983. The next prime is 42391003. The reversal of 42390997 is 79909324.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 42390997 - 2¹¹ = 42388949 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 (42390917) 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, 1926853 + ... + 1926874.

It is an arithmetic number, because the mean of its divisors is an integer number (11561184).

Almost surely, 2^42390997 is an apocalyptic number.

It is an amenable number.

42390997 is a deficient number, since it is larger than the sum of its proper divisors (3853739).

42390997 is a wasteful number, since it uses less digits than its factorization.

42390997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3853738.

The product of its (nonzero) digits is 122472, while the sum is 43.

The square root of 42390997 is about 6510.8368893714. The cubic root of 42390997 is about 348.6779979224.

The spelling of 42390997 in words is "forty-two million, three hundred ninety thousand, nine hundred ninety-seven".