1256342261 has 8 divisors (see below), whose sum is σ = 1261040640. Its totient is φ = 1251652032.

The previous prime is 1256342207. The next prime is 1256342281. The reversal of 1256342261 is 1622436521.

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

It is a cyclic number.

It is not a de Polignac number, because 1256342261 - 2¹⁴ = 1256325877 is a prime.

It is a super-3 number, since 3×1256342261³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1256342201) 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, 569186 + ... + 571388.

It is an arithmetic number, because the mean of its divisors is an integer number (157630080).

Almost surely, 2^1256342261 is an apocalyptic number.

It is an amenable number.

1256342261 is a deficient number, since it is larger than the sum of its proper divisors (4698379).

1256342261 is a wasteful number, since it uses less digits than its factorization.

1256342261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4075.

The product of its digits is 17280, while the sum is 32.

The square root of 1256342261 is about 35444.9186908363. The cubic root of 1256342261 is about 1079.0361373555.

Adding to 1256342261 its reverse (1622436521), we get a palindrome (2878778782).

The spelling of 1256342261 in words is "one billion, two hundred fifty-six million, three hundred forty-two thousand, two hundred sixty-one".