21601491085 has 16 divisors (see below), whose sum is σ = 26127205632. Its totient is φ = 17144769600.

The previous prime is 21601491073. The next prime is 21601491103. The reversal of 21601491085 is 58019410612.

It is not a de Polignac number, because 21601491085 - 2¹⁷ = 21601360013 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 302140 + ... + 366730.

It is an arithmetic number, because the mean of its divisors is an integer number (1632950352).

Almost surely, 2^21601491085 is an apocalyptic number.

It is an amenable number.

21601491085 is a deficient number, since it is larger than the sum of its proper divisors (4525714547).

21601491085 is a wasteful number, since it uses less digits than its factorization.

21601491085 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65124.

The product of its (nonzero) digits is 17280, while the sum is 37.

The spelling of 21601491085 in words is "twenty-one billion, six hundred one million, four hundred ninety-one thousand, eighty-five".