139521873 has 8 divisors (see below), whose sum is σ = 196972128. Its totient is φ = 87543104.

The previous prime is 139521869. The next prime is 139521881. The reversal of 139521873 is 378125931.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 139521873 - 2² = 139521869 is a prime.

It is not an unprimeable number, because it can be changed into a prime (139521373) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1367811 + ... + 1367912.

It is an arithmetic number, because the mean of its divisors is an integer number (24621516).

Almost surely, 2^139521873 is an apocalyptic number.

It is an amenable number.

139521873 is a deficient number, since it is larger than the sum of its proper divisors (57450255).

139521873 is a wasteful number, since it uses less digits than its factorization.

139521873 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2735743.

The product of its digits is 45360, while the sum is 39.

The square root of 139521873 is about 11811.9377326500. The cubic root of 139521873 is about 518.6576236924.

The spelling of 139521873 in words is "one hundred thirty-nine million, five hundred twenty-one thousand, eight hundred seventy-three".