138691472 has 40 divisors (see below), whose sum is σ = 281660544. Its totient is φ = 66032384.

The previous prime is 138691453. The next prime is 138691481. The reversal of 138691472 is 274196831.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 96068 + ... + 97500.

Almost surely, 2^138691472 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138691472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (140830272).

138691472 is an abundant number, since it is smaller than the sum of its proper divisors (142969072).

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

138691472 is a wasteful number, since it uses less digits than its factorization.

138691472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1727 (or 1721 counting only the distinct ones).

The product of its digits is 72576, while the sum is 41.

The square root of 138691472 is about 11776.7343521029. The cubic root of 138691472 is about 517.6265999085.

The spelling of 138691472 in words is "one hundred thirty-eight million, six hundred ninety-one thousand, four hundred seventy-two".