138763531 has 4 divisors (see below), whose sum is σ = 144796752. Its totient is φ = 132730312.

The previous prime is 138763529. The next prime is 138763553. The reversal of 138763531 is 135367831.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 138763531 - 2¹ = 138763529 is a prime.

It is a super-2 number, since 2×138763531² = 38510635071175922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138763931) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3016576 + ... + 3016621.

It is an arithmetic number, because the mean of its divisors is an integer number (36199188).

Almost surely, 2^138763531 is an apocalyptic number.

138763531 is a deficient number, since it is larger than the sum of its proper divisors (6033221).

138763531 is an equidigital number, since it uses as much as digits as its factorization.

138763531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6033220.

The product of its digits is 45360, while the sum is 37.

The square root of 138763531 is about 11779.7933343501. The cubic root of 138763531 is about 517.7162309835.

The spelling of 138763531 in words is "one hundred thirty-eight million, seven hundred sixty-three thousand, five hundred thirty-one".