16681951 has 8 divisors (see below), whose sum is σ = 19598544. Its totient is φ = 13998720.

The previous prime is 16681949. The next prime is 16681991. The reversal of 16681951 is 15918661.

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 16681951 - 2¹ = 16681949 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 16681951.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16681901) 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, 58186 + ... + 58471.

It is an arithmetic number, because the mean of its divisors is an integer number (2449818).

Almost surely, 2^16681951 is an apocalyptic number.

16681951 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

16681951 is a deficient number, since it is larger than the sum of its proper divisors (2916593).

16681951 is a wasteful number, since it uses less digits than its factorization.

16681951 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116681.

The product of its digits is 12960, while the sum is 37.

The square root of 16681951 is about 4084.3544165510. The cubic root of 16681951 is about 255.5145371329.

The spelling of 16681951 in words is "sixteen million, six hundred eighty-one thousand, nine hundred fifty-one".