16181397 has 32 divisors (see below), whose sum is σ = 25436160. Its totient is φ = 10145520.

The previous prime is 16181381. The next prime is 16181401. The reversal of 16181397 is 79318161.

16181397 is a `hidden beast` number, since 1 + 618 + 1 + 39 + 7 = 666.

It is not a de Polignac number, because 16181397 - 2⁴ = 16181381 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16181317) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 43908 + ... + 44274.

It is an arithmetic number, because the mean of its divisors is an integer number (794880).

Almost surely, 2^16181397 is an apocalyptic number.

It is an amenable number.

16181397 is a deficient number, since it is larger than the sum of its proper divisors (9254763).

16181397 is a wasteful number, since it uses less digits than its factorization.

16181397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 470 (or 464 counting only the distinct ones).

The product of its digits is 9072, while the sum is 36.

The square root of 16181397 is about 4022.6107194209. The cubic root of 16181397 is about 252.9329083088.

The spelling of 16181397 in words is "sixteen million, one hundred eighty-one thousand, three hundred ninety-seven".