16820697391 has 8 divisors (see below), whose sum is σ = 17279030160. Its totient is φ = 16362560448.

The previous prime is 16820697367. The next prime is 16820697403. The reversal of 16820697391 is 19379602861.

It is a happy number.

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 16820697391 - 2¹⁹ = 16820173103 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 (16820697331) 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, 134400 + ... + 227386.

It is an arithmetic number, because the mean of its divisors is an integer number (2159878770).

Almost surely, 2^16820697391 is an apocalyptic number.

16820697391 is a deficient number, since it is larger than the sum of its proper divisors (458332769).

16820697391 is an equidigital number, since it uses as much as digits as its factorization.

16820697391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97913.

The product of its (nonzero) digits is 979776, while the sum is 52.

The spelling of 16820697391 in words is "sixteen billion, eight hundred twenty million, six hundred ninety-seven thousand, three hundred ninety-one".