16981405 has 16 divisors (see below), whose sum is σ = 23393664. Its totient is φ = 11592000.

The previous prime is 16981403. The next prime is 16981423. The reversal of 16981405 is 50418961.

It is not a de Polignac number, because 16981405 - 2¹ = 16981403 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16981403) 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, 7819 + ... + 9751.

It is an arithmetic number, because the mean of its divisors is an integer number (1462104).

Almost surely, 2^16981405 is an apocalyptic number.

It is an amenable number.

16981405 is a deficient number, since it is larger than the sum of its proper divisors (6412259).

16981405 is a wasteful number, since it uses less digits than its factorization.

16981405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2196.

The product of its (nonzero) digits is 8640, while the sum is 34.

The square root of 16981405 is about 4120.8500336702. The cubic root of 16981405 is about 257.0343739192.

The spelling of 16981405 in words is "sixteen million, nine hundred eighty-one thousand, four hundred five".