137209381 has 2 divisors, whose sum is σ = 137209382. Its totient is φ = 137209380.

The previous prime is 137209351. The next prime is 137209427. The reversal of 137209381 is 183902731.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 107952100 + 29257281 = 10390^2 + 5409^2 .

It is a cyclic number.

It is not a de Polignac number, because 137209381 - 2⁵ = 137209349 is a prime.

It is a super-2 number, since 2×137209381² = 37652828468806322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (137209351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 68604690 + 68604691.

It is an arithmetic number, because the mean of its divisors is an integer number (68604691).

Almost surely, 2^137209381 is an apocalyptic number.

It is an amenable number.

137209381 is a deficient number, since it is larger than the sum of its proper divisors (1).

137209381 is an equidigital number, since it uses as much as digits as its factorization.

137209381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9072, while the sum is 34.

The square root of 137209381 is about 11713.6408089031. The cubic root of 137209381 is about 515.7761646096.

The spelling of 137209381 in words is "one hundred thirty-seven million, two hundred nine thousand, three hundred eighty-one".