31428057 has 4 divisors (see below), whose sum is σ = 41904080. Its totient is φ = 20952036.

The previous prime is 31428049. The next prime is 31428073. The reversal of 31428057 is 75082413.

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 not a de Polignac number, because 31428057 - 2³ = 31428049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31428037) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5238007 + ... + 5238012.

It is an arithmetic number, because the mean of its divisors is an integer number (10476020).

Almost surely, 2^31428057 is an apocalyptic number.

It is an amenable number.

31428057 is a deficient number, since it is larger than the sum of its proper divisors (10476023).

31428057 is a wasteful number, since it uses less digits than its factorization.

31428057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10476022.

The product of its (nonzero) digits is 6720, while the sum is 30.

The square root of 31428057 is about 5606.0732246377. The cubic root of 31428057 is about 315.5773638790.

The spelling of 31428057 in words is "thirty-one million, four hundred twenty-eight thousand, fifty-seven".