16681970 has 8 divisors (see below), whose sum is σ = 30027564. Its totient is φ = 6672784.

The previous prime is 16681949. The next prime is 16681991. The reversal of 16681970 is 7918661.

It is an interprime number because it is at equal distance from previous prime (16681949) and next prime (16681991).

It can be written as a sum of positive squares in 2 ways, for example, as 16313521 + 368449 = 4039^2 + 607^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 834089 + ... + 834108.

Almost surely, 2^16681970 is an apocalyptic number.

16681970 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

16681970 is a deficient number, since it is larger than the sum of its proper divisors (13345594).

16681970 is a wasteful number, since it uses less digits than its factorization.

16681970 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1668204.

The product of its (nonzero) digits is 18144, while the sum is 38.

The square root of 16681970 is about 4084.3567424994. The cubic root of 16681970 is about 255.5146341394.

The spelling of 16681970 in words is "sixteen million, six hundred eighty-one thousand, nine hundred seventy".