31405225 has 6 divisors (see below), whose sum is σ = 38942510. Its totient is φ = 25124160.

The previous prime is 31405219. The next prime is 31405277. The reversal of 31405225 is 52250413.

It can be written as a sum of positive squares in 3 ways, for example, as 2374681 + 29030544 = 1541^2 + 5388^2 .

It is not a de Polignac number, because 31405225 - 2¹⁷ = 31274153 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31405196 and 31405205.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 628080 + ... + 628129.

Almost surely, 2^31405225 is an apocalyptic number.

It is an amenable number.

31405225 is a deficient number, since it is larger than the sum of its proper divisors (7537285).

31405225 is a wasteful number, since it uses less digits than its factorization.

31405225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1256219 (or 1256214 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 22.

The square root of 31405225 is about 5604.0364916728. The cubic root of 31405225 is about 315.5009246651.

Adding to 31405225 its reverse (52250413), we get a palindrome (83655638).

The spelling of 31405225 in words is "thirty-one million, four hundred five thousand, two hundred twenty-five".