31397738 has 16 divisors (see below), whose sum is σ = 48335616. Its totient is φ = 15291360.

The previous prime is 31397713. The next prime is 31397767. The reversal of 31397738 is 83779313.

It is a junction number, because it is equal to n+sod(n) for n = 31397695 and 31397704.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10823 + ... + 13413.

It is an arithmetic number, because the mean of its divisors is an integer number (3020976).

Almost surely, 2^31397738 is an apocalyptic number.

31397738 is a deficient number, since it is larger than the sum of its proper divisors (16937878).

31397738 is a wasteful number, since it uses less digits than its factorization.

31397738 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2749.

The product of its digits is 95256, while the sum is 41.

The square root of 31397738 is about 5603.3684512086. The cubic root of 31397738 is about 315.4758508846.

The spelling of 31397738 in words is "thirty-one million, three hundred ninety-seven thousand, seven hundred thirty-eight".