17139991 has 16 divisors (see below), whose sum is σ = 20049408. Its totient is φ = 14493600.

The previous prime is 17139989. The next prime is 17140021. The reversal of 17139991 is 19993171.

It is not a de Polignac number, because 17139991 - 2¹ = 17139989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (17139901) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8446 + ... + 10276.

It is an arithmetic number, because the mean of its divisors is an integer number (1253088).

Almost surely, 2^17139991 is an apocalyptic number.

17139991 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

17139991 is a deficient number, since it is larger than the sum of its proper divisors (2909417).

17139991 is a wasteful number, since it uses less digits than its factorization.

17139991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1902.

The product of its digits is 15309, while the sum is 40.

The square root of 17139991 is about 4140.0472219529. The cubic root of 17139991 is about 257.8320271539.

The spelling of 17139991 in words is "seventeen million, one hundred thirty-nine thousand, nine hundred ninety-one".