137666531 has 2 divisors, whose sum is σ = 137666532. Its totient is φ = 137666530.

The previous prime is 137666491. The next prime is 137666587. The reversal of 137666531 is 135666731.

It is a weak prime.

It is an emirp because it is prime and its reverse (135666731) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-137666531 is a prime.

It is a super-2 number, since 2×137666531² = 37904147515147922, which contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (137366531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 68833265 + 68833266.

It is an arithmetic number, because the mean of its divisors is an integer number (68833266).

Almost surely, 2^137666531 is an apocalyptic number.

137666531 is a deficient number, since it is larger than the sum of its proper divisors (1).

137666531 is an equidigital number, since it uses as much as digits as its factorization.

137666531 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 68040, while the sum is 38.

The square root of 137666531 is about 11733.1381565206. The cubic root of 137666531 is about 516.3483453474.

The spelling of 137666531 in words is "one hundred thirty-seven million, six hundred sixty-six thousand, five hundred thirty-one".