21916058991 has 16 divisors (see below), whose sum is σ = 31339751040. Its totient is φ = 13580555040.

The previous prime is 21916058951. The next prime is 21916058999. The reversal of 21916058991 is 19985061912.

It is not a de Polignac number, because 21916058991 - 2⁷ = 21916058863 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21916058999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3624265 + ... + 3630306.

It is an arithmetic number, because the mean of its divisors is an integer number (1958734440).

Almost surely, 2^21916058991 is an apocalyptic number.

21916058991 is a deficient number, since it is larger than the sum of its proper divisors (9423692049).

21916058991 is a wasteful number, since it uses less digits than its factorization.

21916058991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7254646.

The product of its (nonzero) digits is 349920, while the sum is 51.

The spelling of 21916058991 in words is "twenty-one billion, nine hundred sixteen million, fifty-eight thousand, nine hundred ninety-one".