66139271 has 8 divisors (see below), whose sum is σ = 72255888. Its totient is φ = 60040000.

The previous prime is 66139261. The next prime is 66139277. The reversal of 66139271 is 17293166.

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 66139271 - 2¹⁴ = 66122887 is a prime.

It is a super-2 number, since 2×66139271² = 8748806336822882, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66139277) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4421 + ... + 12321.

It is an arithmetic number, because the mean of its divisors is an integer number (9031986).

Almost surely, 2^66139271 is an apocalyptic number.

66139271 is a deficient number, since it is larger than the sum of its proper divisors (6116617).

66139271 is a wasteful number, since it uses less digits than its factorization.

66139271 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8673.

The product of its digits is 13608, while the sum is 35.

The square root of 66139271 is about 8132.6054250775. The cubic root of 66139271 is about 404.4080586863.

The spelling of 66139271 in words is "sixty-six million, one hundred thirty-nine thousand, two hundred seventy-one".