137443661 has 2 divisors, whose sum is σ = 137443662. Its totient is φ = 137443660.

The previous prime is 137443643. The next prime is 137443693. The reversal of 137443661 is 166344731.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 106296100 + 31147561 = 10310^2 + 5581^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-137443661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (137443261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 68721830 + 68721831.

It is an arithmetic number, because the mean of its divisors is an integer number (68721831).

Almost surely, 2^137443661 is an apocalyptic number.

It is an amenable number.

137443661 is a deficient number, since it is larger than the sum of its proper divisors (1).

137443661 is an equidigital number, since it uses as much as digits as its factorization.

137443661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36288, while the sum is 35.

The square root of 137443661 is about 11723.6368503976. The cubic root of 137443661 is about 516.0695540017.

The spelling of 137443661 in words is "one hundred thirty-seven million, four hundred forty-three thousand, six hundred sixty-one".