1340806261 has 2 divisors, whose sum is σ = 1340806262. Its totient is φ = 1340806260.

The previous prime is 1340806253. The next prime is 1340806267. The reversal of 1340806261 is 1626080431.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1242915025 + 97891236 = 35255^2 + 9894^2 .

It is a cyclic number.

It is not a de Polignac number, because 1340806261 - 2³ = 1340806253 is a prime.

It is a super-2 number, since 2×1340806261² = 3595522859073600242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1340806267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 670403130 + 670403131.

It is an arithmetic number, because the mean of its divisors is an integer number (670403131).

Almost surely, 2^1340806261 is an apocalyptic number.

It is an amenable number.

1340806261 is a deficient number, since it is larger than the sum of its proper divisors (1).

1340806261 is an equidigital number, since it uses as much as digits as its factorization.

1340806261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6912, while the sum is 31.

The square root of 1340806261 is about 36617.0214654333. The cubic root of 1340806261 is about 1102.6948419444.

Adding to 1340806261 its reverse (1626080431), we get a palindrome (2966886692).

The spelling of 1340806261 in words is "one billion, three hundred forty million, eight hundred six thousand, two hundred sixty-one".