139081491 has 6 divisors (see below), whose sum is σ = 200895500. Its totient is φ = 92720988.

The previous prime is 139081451. The next prime is 139081499. The reversal of 139081491 is 194180931.

139081491 is a `hidden beast` number, since 1 + 3 + 90 + 81 + 491 = 666.

It is not a de Polignac number, because 139081491 - 2⁷ = 139081363 is a prime.

It is a super-2 number, since 2×139081491² = 38687322277566162, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (139081499) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 7726741 + ... + 7726758.

Almost surely, 2^139081491 is an apocalyptic number.

139081491 is a deficient number, since it is larger than the sum of its proper divisors (61814009).

139081491 is a wasteful number, since it uses less digits than its factorization.

139081491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15453505 (or 15453502 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 36.

The square root of 139081491 is about 11793.2816043712. The cubic root of 139081491 is about 518.1113575730. Note that the first 3 decimals are identical.

The spelling of 139081491 in words is "one hundred thirty-nine million, eighty-one thousand, four hundred ninety-one".