138628577 has 2 divisors, whose sum is σ = 138628578. Its totient is φ = 138628576.

The previous prime is 138628573. The next prime is 138628597. The reversal of 138628577 is 775826831.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 96845281 + 41783296 = 9841^2 + 6464^2 .

It is a cyclic number.

It is not a de Polignac number, because 138628577 - 2² = 138628573 is a prime.

It is a super-2 number, since 2×138628577² = 38435764722089858, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (138628571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69314288 + 69314289.

It is an arithmetic number, because the mean of its divisors is an integer number (69314289).

Almost surely, 2^138628577 is an apocalyptic number.

It is an amenable number.

138628577 is a deficient number, since it is larger than the sum of its proper divisors (1).

138628577 is an equidigital number, since it uses as much as digits as its factorization.

138628577 is an evil number, because the sum of its binary digits is even.

The product of its digits is 564480, while the sum is 47.

The square root of 138628577 is about 11774.0637419712. The cubic root of 138628577 is about 517.5483421587.

The spelling of 138628577 in words is "one hundred thirty-eight million, six hundred twenty-eight thousand, five hundred seventy-seven".