1261390 has 32 divisors (see below), whose sum is σ = 2532096. Its totient is φ = 449280.

The previous prime is 1261387. The next prime is 1261411. The reversal of 1261390 is 931621.

1261390 = T₁₁₆ + T₁₁₇ + ... + T₂₀₈.

It is a super-2 number, since 2×1261390² = 3182209464200, which contains 22 as substring.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3874 + ... + 4186.

It is an arithmetic number, because the mean of its divisors is an integer number (79128).

2^1261390 is an apocalyptic number.

1261390 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1261390 is an abundant number, since it is smaller than the sum of its proper divisors (1270706).

1261390 is a wasteful number, since it uses less digits than its factorization.

1261390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 364.

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 1261390 is about 1123.1162005777. The cubic root of 1261390 is about 108.0479325415.

The spelling of 1261390 in words is "one million, two hundred sixty-one thousand, three hundred ninety".