31420447 has 2 divisors, whose sum is σ = 31420448. Its totient is φ = 31420446.

The previous prime is 31420409. The next prime is 31420457. The reversal of 31420447 is 74402413.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 31420447 - 2¹⁵ = 31387679 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31420457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15710223 + 15710224.

It is an arithmetic number, because the mean of its divisors is an integer number (15710224).

Almost surely, 2^31420447 is an apocalyptic number.

31420447 is a deficient number, since it is larger than the sum of its proper divisors (1).

31420447 is an equidigital number, since it uses as much as digits as its factorization.

31420447 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 31420447 is about 5605.3944553439. The cubic root of 31420447 is about 315.5518904875.

The spelling of 31420447 in words is "thirty-one million, four hundred twenty thousand, four hundred forty-seven".