31021930 has 8 divisors (see below), whose sum is σ = 55839492. Its totient is φ = 12408768.

The previous prime is 31021897. The next prime is 31021931. The reversal of 31021930 is 3912013.

It can be written as a sum of positive squares in 2 ways, for example, as 29365561 + 1656369 = 5419^2 + 1287^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 31021898 and 31021907.

It is not an unprimeable number, because it can be changed into a prime (31021931) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1551087 + ... + 1551106.

Almost surely, 2^31021930 is an apocalyptic number.

31021930 is a deficient number, since it is larger than the sum of its proper divisors (24817562).

31021930 is a wasteful number, since it uses less digits than its factorization.

31021930 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3102200.

The product of its (nonzero) digits is 162, while the sum is 19.

The square root of 31021930 is about 5569.7333867969. The cubic root of 31021930 is about 314.2121235609.

Adding to 31021930 its reverse (3912013), we get a palindrome (34933943).

It can be divided in two parts, 310219 and 30, that added together give a square (310249 = 557²).

The spelling of 31021930 in words is "thirty-one million, twenty-one thousand, nine hundred thirty".