31428143 has 8 divisors (see below), whose sum is σ = 32919648. Its totient is φ = 29947104.

The previous prime is 31428139. The next prime is 31428149. The reversal of 31428143 is 34182413.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 31428143 - 2² = 31428139 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 (31428149) 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 7 ways as a sum of consecutive naturals, for example, 3905 + ... + 8837.

It is an arithmetic number, because the mean of its divisors is an integer number (4114956).

Almost surely, 2^31428143 is an apocalyptic number.

31428143 is a deficient number, since it is larger than the sum of its proper divisors (1491505).

31428143 is a wasteful number, since it uses less digits than its factorization.

31428143 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5233.

The product of its digits is 2304, while the sum is 26.

The square root of 31428143 is about 5606.0808948855. The cubic root of 31428143 is about 315.5776517283.

Multiplying 31428143 by its sum of digits (26), we get a palindrome (817131718).

The spelling of 31428143 in words is "thirty-one million, four hundred twenty-eight thousand, one hundred forty-three".