138432971 has 2 divisors, whose sum is σ = 138432972. Its totient is φ = 138432970.

The previous prime is 138432937. The next prime is 138432977. The reversal of 138432971 is 179234831.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 138432971 - 2¹⁰ = 138431947 is a prime.

It is not a weakly prime, because it can be changed into another prime (138432977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69216485 + 69216486.

It is an arithmetic number, because the mean of its divisors is an integer number (69216486).

Almost surely, 2^138432971 is an apocalyptic number.

138432971 is a deficient number, since it is larger than the sum of its proper divisors (1).

138432971 is an equidigital number, since it uses as much as digits as its factorization.

138432971 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36288, while the sum is 38.

The square root of 138432971 is about 11765.7541619736. The cubic root of 138432971 is about 517.3048060007.

The spelling of 138432971 in words is "one hundred thirty-eight million, four hundred thirty-two thousand, nine hundred seventy-one".