138021707 has 2 divisors, whose sum is σ = 138021708. Its totient is φ = 138021706.

The previous prime is 138021673. The next prime is 138021713. The reversal of 138021707 is 707120831.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 138021707 - 2¹⁶ = 137956171 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 138021707.

It is not a weakly prime, because it can be changed into another prime (138021307) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69010853 + 69010854.

It is an arithmetic number, because the mean of its divisors is an integer number (69010854).

Almost surely, 2^138021707 is an apocalyptic number.

138021707 is a deficient number, since it is larger than the sum of its proper divisors (1).

138021707 is an equidigital number, since it uses as much as digits as its factorization.

138021707 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2352, while the sum is 29.

The square root of 138021707 is about 11748.2639994171. The cubic root of 138021707 is about 516.7920190241.

The spelling of 138021707 in words is "one hundred thirty-eight million, twenty-one thousand, seven hundred seven".