31440427 has 2 divisors, whose sum is σ = 31440428. Its totient is φ = 31440426.

The previous prime is 31440419. The next prime is 31440449. The reversal of 31440427 is 72404413.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31440427 - 2³ = 31440419 is a prime.

It is not a weakly prime, because it can be changed into another prime (31440457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15720213 + 15720214.

It is an arithmetic number, because the mean of its divisors is an integer number (15720214).

Almost surely, 2^31440427 is an apocalyptic number.

31440427 is a deficient number, since it is larger than the sum of its proper divisors (1).

31440427 is an equidigital number, since it uses as much as digits as its factorization.

31440427 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2688, while the sum is 25.

The square root of 31440427 is about 5607.1763838852. The cubic root of 31440427 is about 315.6187619196.

The spelling of 31440427 in words is "thirty-one million, four hundred forty thousand, four hundred twenty-seven".