16905340921 has 8 divisors (see below), whose sum is σ = 19388661824. Its totient is φ = 14439088080.

The previous prime is 16905340901. The next prime is 16905340927. The reversal of 16905340921 is 12904350961.

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 16905340921 - 2⁹ = 16905340409 is a prime.

It is a super-3 number, since 3×16905340921³ (a number of 32 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (16905340927) 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, 4264890 + ... + 4268851.

It is an arithmetic number, because the mean of its divisors is an integer number (2423582728).

Almost surely, 2^16905340921 is an apocalyptic number.

It is an amenable number.

16905340921 is a deficient number, since it is larger than the sum of its proper divisors (2483320903).

16905340921 is an equidigital number, since it uses as much as digits as its factorization.

16905340921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8534031.

The product of its (nonzero) digits is 58320, while the sum is 40.

The spelling of 16905340921 in words is "sixteen billion, nine hundred five million, three hundred forty thousand, nine hundred twenty-one".