139760721 has 24 divisors (see below), whose sum is σ = 209961024. Its totient is φ = 92903760.

The previous prime is 139760701. The next prime is 139760743. The reversal of 139760721 is 127067931.

It is a happy number.

It is not a de Polignac number, because 139760721 - 2⁹ = 139760209 is a prime.

It is not an unprimeable number, because it can be changed into a prime (139760701) 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, 117751 + ... + 118931.

It is an arithmetic number, because the mean of its divisors is an integer number (8748376).

Almost surely, 2^139760721 is an apocalyptic number.

It is an amenable number.

139760721 is a deficient number, since it is larger than the sum of its proper divisors (70200303).

139760721 is an equidigital number, since it uses as much as digits as its factorization.

139760721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1683 (or 1671 counting only the distinct ones).

The product of its (nonzero) digits is 15876, while the sum is 36.

The square root of 139760721 is about 11822.0438588258. The cubic root of 139760721 is about 518.9534189207.

The spelling of 139760721 in words is "one hundred thirty-nine million, seven hundred sixty thousand, seven hundred twenty-one".