138263731 has 2 divisors, whose sum is σ = 138263732. Its totient is φ = 138263730.

The previous prime is 138263701. The next prime is 138263743. The reversal of 138263731 is 137362831.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 138263731 - 2¹³ = 138255539 is a prime.

It is a super-2 number, since 2×138263731² = 38233718620080722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (138263701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69131865 + 69131866.

It is an arithmetic number, because the mean of its divisors is an integer number (69131866).

Almost surely, 2^138263731 is an apocalyptic number.

138263731 is a deficient number, since it is larger than the sum of its proper divisors (1).

138263731 is an equidigital number, since it uses as much as digits as its factorization.

138263731 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18144, while the sum is 34.

The square root of 138263731 is about 11758.5599033215. The cubic root of 138263731 is about 517.0939112352.

The spelling of 138263731 in words is "one hundred thirty-eight million, two hundred sixty-three thousand, seven hundred thirty-one".