1261931 has 8 divisors (see below), whose sum is σ = 1393200. Its totient is φ = 1133440.

The previous prime is 1261913. The next prime is 1261933. The reversal of 1261931 is 1391621.

It is a happy number.

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

It is a de Polignac number, because none of the positive numbers 2^k-1261931 is a prime.

It is a super-2 number, since 2×1261931² = 3184939697522, 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 = 1261897 and 1261906.

It is not an unprimeable number, because it can be changed into a prime (1261933) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 335 + ... + 1623.

It is an arithmetic number, because the mean of its divisors is an integer number (174150).

2^1261931 is an apocalyptic number.

1261931 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1261931 is a deficient number, since it is larger than the sum of its proper divisors (131269).

1261931 is a wasteful number, since it uses less digits than its factorization.

1261931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1389.

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

The square root of 1261931 is about 1123.3570225000. The cubic root of 1261931 is about 108.0633772960.

The spelling of 1261931 in words is "one million, two hundred sixty-one thousand, nine hundred thirty-one".