137649881 has 2 divisors, whose sum is σ = 137649882. Its totient is φ = 137649880.

The previous prime is 137649823. The next prime is 137649937. The reversal of 137649881 is 188946731.

137649881 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 102839881 + 34810000 = 10141^2 + 5900^2 .

It is a cyclic number.

It is not a de Polignac number, because 137649881 - 2¹⁸ = 137387737 is a prime.

It is a super-2 number, since 2×137649881² = 37894979478628322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (137649821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 68824940 + 68824941.

It is an arithmetic number, because the mean of its divisors is an integer number (68824941).

Almost surely, 2^137649881 is an apocalyptic number.

It is an amenable number.

137649881 is a deficient number, since it is larger than the sum of its proper divisors (1).

137649881 is an equidigital number, since it uses as much as digits as its factorization.

137649881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 290304, while the sum is 47.

The square root of 137649881 is about 11732.4286062179. The cubic root of 137649881 is about 516.3275280229.

The spelling of 137649881 in words is "one hundred thirty-seven million, six hundred forty-nine thousand, eight hundred eighty-one".