138888737 has 8 divisors (see below), whose sum is σ = 150217704. Its totient is φ = 127651968.

The previous prime is 138888707. The next prime is 138888767. The reversal of 138888737 is 737888831.

It is an interprime number because it is at equal distance from previous prime (138888707) and next prime (138888767).

It can be written as a sum of positive squares in 4 ways, for example, as 14432401 + 124456336 = 3799^2 + 11156^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 138888737 - 2⁸ = 138888481 is a prime.

It is not an unprimeable number, because it can be changed into a prime (138888707) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19898 + ... + 25955.

It is an arithmetic number, because the mean of its divisors is an integer number (18777213).

Almost surely, 2^138888737 is an apocalyptic number.

It is an amenable number.

138888737 is a deficient number, since it is larger than the sum of its proper divisors (11328967).

138888737 is a wasteful number, since it uses less digits than its factorization.

138888737 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46099.

The product of its digits is 1806336, while the sum is 53.

The square root of 138888737 is about 11785.1065756742. The cubic root of 138888737 is about 517.8718955439.

The spelling of 138888737 in words is "one hundred thirty-eight million, eight hundred eighty-eight thousand, seven hundred thirty-seven".