137356781 has 2 divisors, whose sum is σ = 137356782. Its totient is φ = 137356780.

The previous prime is 137356777. The next prime is 137356837. The reversal of 137356781 is 187653731.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 102191881 + 35164900 = 10109^2 + 5930^2 .

It is an emirp because it is prime and its reverse (187653731) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 137356781 - 2² = 137356777 is a prime.

It is a super-2 number, since 2×137356781² = 37733770573363922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (137356721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 68678390 + 68678391.

It is an arithmetic number, because the mean of its divisors is an integer number (68678391).

Almost surely, 2^137356781 is an apocalyptic number.

It is an amenable number.

137356781 is a deficient number, since it is larger than the sum of its proper divisors (1).

137356781 is an equidigital number, since it uses as much as digits as its factorization.

137356781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 105840, while the sum is 41.

The square root of 137356781 is about 11719.9309298306. The cubic root of 137356781 is about 515.9607928967.

The spelling of 137356781 in words is "one hundred thirty-seven million, three hundred fifty-six thousand, seven hundred eighty-one".