138613212661 has 24 divisors (see below), whose sum is σ = 174199620672. Its totient is φ = 107964436800.

The previous prime is 138613212659. The next prime is 138613212701. The reversal of 138613212661 is 166212316831.

It is not a de Polignac number, because 138613212661 - 2¹ = 138613212659 is a prime.

It is a super-2 number, since 2×138613212661² (a number of 23 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138613212601) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2034006 + ... + 2101048.

It is an arithmetic number, because the mean of its divisors is an integer number (7258317528).

Almost surely, 2^138613212661 is an apocalyptic number.

138613212661 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

138613212661 is a deficient number, since it is larger than the sum of its proper divisors (35586408011).

138613212661 is a wasteful number, since it uses less digits than its factorization.

138613212661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69513 (or 69502 counting only the distinct ones).

The product of its digits is 62208, while the sum is 40.

The spelling of 138613212661 in words is "one hundred thirty-eight billion, six hundred thirteen million, two hundred twelve thousand, six hundred sixty-one".