31443289 has 2 divisors, whose sum is σ = 31443290. Its totient is φ = 31443288.

The previous prime is 31443287. The next prime is 31443299. The reversal of 31443289 is 98234413.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 30691600 + 751689 = 5540^2 + 867^2 .

It is a cyclic number.

It is not a de Polignac number, because 31443289 - 2¹ = 31443287 is a prime.

Together with 31443287, it forms a pair of twin primes.

It is equal to p_1941595 and since 31443289 and 1941595 have the same sum of digits, it is a Honaker prime.

It is a nialpdrome in base 12.

It is not a weakly prime, because it can be changed into another prime (31443287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15721644 + 15721645.

It is an arithmetic number, because the mean of its divisors is an integer number (15721645).

Almost surely, 2^31443289 is an apocalyptic number.

It is an amenable number.

31443289 is a deficient number, since it is larger than the sum of its proper divisors (1).

31443289 is an equidigital number, since it uses as much as digits as its factorization.

31443289 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20736, while the sum is 34.

The square root of 31443289 is about 5607.4315867427. The cubic root of 31443289 is about 315.6283384805.

The spelling of 31443289 in words is "thirty-one million, four hundred forty-three thousand, two hundred eighty-nine".