16961591 has 4 divisors (see below), whose sum is σ = 17032800. Its totient is φ = 16890384.

The previous prime is 16961569. The next prime is 16961611. The reversal of 16961591 is 19516961.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19516961 = 967 ⋅20183.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16961591 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 (16961521) 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, 35246 + ... + 35723.

It is an arithmetic number, because the mean of its divisors is an integer number (4258200).

Almost surely, 2^16961591 is an apocalyptic number.

16961591 is a deficient number, since it is larger than the sum of its proper divisors (71209).

16961591 is an equidigital number, since it uses as much as digits as its factorization.

16961591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71208.

The product of its digits is 14580, while the sum is 38.

The square root of 16961591 is about 4118.4452163407. The cubic root of 16961591 is about 256.9343652888.

The spelling of 16961591 in words is "sixteen million, nine hundred sixty-one thousand, five hundred ninety-one".