16621717087 has 4 divisors (see below), whose sum is σ = 16625543400. Its totient is φ = 16617890776.

The previous prime is 16621716983. The next prime is 16621717093. The reversal of 16621717087 is 78071712661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78071712661 = 5851 ⋅13343311.

It is a cyclic number.

It is not a de Polignac number, because 16621717087 - 2²⁷ = 16487499359 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 (16621712087) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1906633 + ... + 1915330.

It is an arithmetic number, because the mean of its divisors is an integer number (4156385850).

Almost surely, 2^16621717087 is an apocalyptic number.

16621717087 is a deficient number, since it is larger than the sum of its proper divisors (3826313).

16621717087 is an equidigital number, since it uses as much as digits as its factorization.

16621717087 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3826312.

The product of its (nonzero) digits is 197568, while the sum is 46.

The spelling of 16621717087 in words is "sixteen billion, six hundred twenty-one million, seven hundred seventeen thousand, eighty-seven".