1216931 has 6 divisors (see below), whose sum is σ = 1284732. Its totient is φ = 1152540.

The previous prime is 1216913. The next prime is 1216937. The reversal of 1216931 is 1396121.

It is a happy number.

It is not a de Polignac number, because 1216931 - 2⁶ = 1216867 is a prime.

It is a super-2 number, since 2×1216931² = 2961842117522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1216897 and 1216906.

It is not an unprimeable number, because it can be changed into a prime (1216937) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1325 + ... + 2046.

It is an arithmetic number, because the mean of its divisors is an integer number (214122).

2^1216931 is an apocalyptic number.

1216931 is a deficient number, since it is larger than the sum of its proper divisors (67801).

1216931 is an equidigital number, since it uses as much as digits as its factorization.

1216931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3409 (or 3390 counting only the distinct ones).

The product of its digits is 324, while the sum is 23.

The square root of 1216931 is about 1103.1459558916. The cubic root of 1216931 is about 106.7632989335.

It can be divided in two parts, 1216 and 931, that multiplied together give a square (1132096 = 1064²).

The spelling of 1216931 in words is "one million, two hundred sixteen thousand, nine hundred thirty-one".