42872257 has 4 divisors (see below), whose sum is σ = 42914560. Its totient is φ = 42829956.

The previous prime is 42872251. The next prime is 42872261. The reversal of 42872257 is 75227824.

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-42872257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42872251) 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, 19593 + ... + 21670.

It is an arithmetic number, because the mean of its divisors is an integer number (10728640).

Almost surely, 2^42872257 is an apocalyptic number.

It is an amenable number.

42872257 is a deficient number, since it is larger than the sum of its proper divisors (42303).

42872257 is a wasteful number, since it uses less digits than its factorization.

42872257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42302.

The product of its digits is 62720, while the sum is 37.

The square root of 42872257 is about 6547.6909670509. The cubic root of 42872257 is about 349.9925358952.

The spelling of 42872257 in words is "forty-two million, eight hundred seventy-two thousand, two hundred fifty-seven".