138594027421 has 2 divisors, whose sum is σ = 138594027422. Its totient is φ = 138594027420.

The previous prime is 138594027409. The next prime is 138594027427. The reversal of 138594027421 is 124720495831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 138543261796 + 50765625 = 372214^2 + 7125^2 .

It is a cyclic number.

It is not a de Polignac number, because 138594027421 - 2⁵ = 138594027389 is a prime.

It is a super-2 number, since 2×138594027421² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138594027427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69297013710 + 69297013711.

It is an arithmetic number, because the mean of its divisors is an integer number (69297013711).

Almost surely, 2^138594027421 is an apocalyptic number.

It is an amenable number.

138594027421 is a deficient number, since it is larger than the sum of its proper divisors (1).

138594027421 is an equidigital number, since it uses as much as digits as its factorization.

138594027421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 483840, while the sum is 46.

The spelling of 138594027421 in words is "one hundred thirty-eight billion, five hundred ninety-four million, twenty-seven thousand, four hundred twenty-one".