31400869 has 2 divisors, whose sum is σ = 31400870. Its totient is φ = 31400868.

The previous prime is 31400867. The next prime is 31400893. The reversal of 31400869 is 96800413.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26936100 + 4464769 = 5190^2 + 2113^2 .

It is an emirp because it is prime and its reverse (96800413) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31400869 - 2¹ = 31400867 is a prime.

It is a super-2 number, since 2×31400869² = 1972029147910322, which contains 22 as substring.

Together with 31400867, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31400869.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31400867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15700434 + 15700435.

It is an arithmetic number, because the mean of its divisors is an integer number (15700435).

Almost surely, 2^31400869 is an apocalyptic number.

It is an amenable number.

31400869 is a deficient number, since it is larger than the sum of its proper divisors (1).

31400869 is an equidigital number, since it uses as much as digits as its factorization.

31400869 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 31400869 is about 5603.6478297623. The cubic root of 31400869 is about 315.4863370121.

The spelling of 31400869 in words is "thirty-one million, four hundred thousand, eight hundred sixty-nine".