139866161 has 4 divisors (see below), whose sum is σ = 139911024. Its totient is φ = 139821300.

The previous prime is 139866131. The next prime is 139866193. The reversal of 139866161 is 161668931.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 139866161 - 2¹⁴ = 139849777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (139866131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17375 + ... + 24116.

It is an arithmetic number, because the mean of its divisors is an integer number (34977756).

Almost surely, 2^139866161 is an apocalyptic number.

It is an amenable number.

139866161 is a deficient number, since it is larger than the sum of its proper divisors (44863).

139866161 is an equidigital number, since it uses as much as digits as its factorization.

139866161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44862.

The product of its digits is 46656, while the sum is 41.

The square root of 139866161 is about 11826.5024838284. The cubic root of 139866161 is about 519.0838911865.

The spelling of 139866161 in words is "one hundred thirty-nine million, eight hundred sixty-six thousand, one hundred sixty-one".