42272561 has 4 divisors (see below), whose sum is σ = 43636224. Its totient is φ = 40908900.

The previous prime is 42272513. The next prime is 42272563. The reversal of 42272561 is 16527224.

It is a happy number.

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 a de Polignac number, because none of the positive numbers 2^k-42272561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42272563) 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, 681785 + ... + 681846.

It is an arithmetic number, because the mean of its divisors is an integer number (10909056).

Almost surely, 2^42272561 is an apocalyptic number.

It is an amenable number.

42272561 is a deficient number, since it is larger than the sum of its proper divisors (1363663).

42272561 is a wasteful number, since it uses less digits than its factorization.

42272561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1363662.

The product of its digits is 6720, while the sum is 29.

The square root of 42272561 is about 6501.7352299213. The cubic root of 42272561 is about 348.3529717846.

Adding to 42272561 its reverse (16527224), we get a palindrome (58799785).

The spelling of 42272561 in words is "forty-two million, two hundred seventy-two thousand, five hundred sixty-one".