42990161 has 4 divisors (see below), whose sum is σ = 45519012. Its totient is φ = 40461312.

The previous prime is 42990137. The next prime is 42990187. The reversal of 42990161 is 16109924.

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

It can be written as a sum of positive squares in 2 ways, for example, as 32947600 + 10042561 = 5740^2 + 3169^2 .

It is a cyclic number.

It is not a de Polignac number, because 42990161 - 2⁶ = 42990097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42990121) 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, 1264400 + ... + 1264433.

It is an arithmetic number, because the mean of its divisors is an integer number (11379753).

Almost surely, 2^42990161 is an apocalyptic number.

It is an amenable number.

42990161 is a deficient number, since it is larger than the sum of its proper divisors (2528851).

42990161 is a wasteful number, since it uses less digits than its factorization.

42990161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2528850.

The product of its (nonzero) digits is 3888, while the sum is 32.

The square root of 42990161 is about 6556.6882646653. The cubic root of 42990161 is about 350.3130831217.

The spelling of 42990161 in words is "forty-two million, nine hundred ninety thousand, one hundred sixty-one".