16780397 has 4 divisors (see below), whose sum is σ = 16818720. Its totient is φ = 16742076.

The previous prime is 16780391. The next prime is 16780399. The reversal of 16780397 is 79308761.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 16780397 - 2⁴ = 16780381 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 (16780391) 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, 18497 + ... + 19382.

It is an arithmetic number, because the mean of its divisors is an integer number (4204680).

Almost surely, 2^16780397 is an apocalyptic number.

It is an amenable number.

16780397 is a deficient number, since it is larger than the sum of its proper divisors (38323).

16780397 is an equidigital number, since it uses as much as digits as its factorization.

16780397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38322.

The product of its (nonzero) digits is 63504, while the sum is 41.

The square root of 16780397 is about 4096.3882872599. The cubic root of 16780397 is about 256.0161783802.

The spelling of 16780397 in words is "sixteen million, seven hundred eighty thousand, three hundred ninety-seven".