31401431 has 4 divisors (see below), whose sum is σ = 33248592. Its totient is φ = 29554272.

The previous prime is 31401407. The next prime is 31401439. The reversal of 31401431 is 13410413.

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

It is a cyclic number.

It is not a de Polignac number, because 31401431 - 2¹⁸ = 31139287 is a prime.

It is a super-2 number, since 2×31401431² = 1972099737695522, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17), and also a Moran number because the ratio is a prime number: 1847143 = 31401431 / (3 + 1 + 4 + 0 + 1 + 4 + 3 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31401439) 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, 923555 + ... + 923588.

It is an arithmetic number, because the mean of its divisors is an integer number (8312148).

Almost surely, 2^31401431 is an apocalyptic number.

31401431 is a deficient number, since it is larger than the sum of its proper divisors (1847161).

31401431 is a wasteful number, since it uses less digits than its factorization.

31401431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1847160.

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 31401431 is about 5603.6979754444. The cubic root of 31401431 is about 315.4882191497.

Adding to 31401431 its reverse (13410413), we get a palindrome (44811844).

The spelling of 31401431 in words is "thirty-one million, four hundred one thousand, four hundred thirty-one".