3136781 has 2 divisors, whose sum is σ = 3136782. Its totient is φ = 3136780.

The previous prime is 3136769. The next prime is 3136799. The reversal of 3136781 is 1876313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1779556 + 1357225 = 1334^2 + 1165^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3136781 is a prime.

It is a super-2 number, since 2×3136781² = 19678790083922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3132781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1568390 + 1568391.

It is an arithmetic number, because the mean of its divisors is an integer number (1568391).

Almost surely, 2^3136781 is an apocalyptic number.

It is an amenable number.

3136781 is a deficient number, since it is larger than the sum of its proper divisors (1).

3136781 is an equidigital number, since it uses as much as digits as its factorization.

3136781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3024, while the sum is 29.

The square root of 3136781 is about 1771.0959883643. The cubic root of 3136781 is about 146.3843784032.

The spelling of 3136781 in words is "three million, one hundred thirty-six thousand, seven hundred eighty-one".