137752781 has 2 divisors, whose sum is σ = 137752782. Its totient is φ = 137752780.

The previous prime is 137752757. The next prime is 137752799. The reversal of 137752781 is 187257731.

137752781 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., 107952100 + 29800681 = 10390^2 + 5459^2 .

It is an emirp because it is prime and its reverse (187257731) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 137752781 - 2¹⁸ = 137490637 is a prime.

It is a super-2 number, since 2×137752781² = 37951657346467922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (137752711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 68876390 + 68876391.

It is an arithmetic number, because the mean of its divisors is an integer number (68876391).

Almost surely, 2^137752781 is an apocalyptic number.

It is an amenable number.

137752781 is a deficient number, since it is larger than the sum of its proper divisors (1).

137752781 is an equidigital number, since it uses as much as digits as its factorization.

137752781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 82320, while the sum is 41.

The square root of 137752781 is about 11736.8130682907. The cubic root of 137752781 is about 516.4561559801.

The spelling of 137752781 in words is "one hundred thirty-seven million, seven hundred fifty-two thousand, seven hundred eighty-one".