138991085632 has 70 divisors (see below), whose sum is σ = 321760051678. Its totient is φ = 59567542272.

The previous prime is 138991085609. The next prime is 138991085633. The reversal of 138991085632 is 236580199831.

It can be written as a sum of positive squares in only one way, i.e., 69598881856 + 69392203776 = 263816^2 + 263424^2 .

It is not an unprimeable number, because it can be changed into a prime (138991085633) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 298593 + ... + 605920.

Almost surely, 2^138991085632 is an apocalyptic number.

It is an amenable number.

138991085632 is an abundant number, since it is smaller than the sum of its proper divisors (182768966046).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

138991085632 is an frugal number, since it uses more digits than its factorization.

138991085632 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 904553 (or 904522 counting only the distinct ones).

The product of its (nonzero) digits is 2799360, while the sum is 55.

The spelling of 138991085632 in words is "one hundred thirty-eight billion, nine hundred ninety-one million, eighty-five thousand, six hundred thirty-two".