21313991061 has 24 divisors (see below), whose sum is σ = 34743814560. Its totient is φ = 12472135200.

The previous prime is 21313991053. The next prime is 21313991087. The reversal of 21313991061 is 16019931312.

It is not a de Polignac number, because 21313991061 - 2³ = 21313991053 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21313991011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3709075 + ... + 3714816.

It is an arithmetic number, because the mean of its divisors is an integer number (1447658940).

Almost surely, 2^21313991061 is an apocalyptic number.

It is an amenable number.

21313991061 is a deficient number, since it is larger than the sum of its proper divisors (13429823499).

21313991061 is a wasteful number, since it uses less digits than its factorization.

21313991061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7423937 (or 7423934 counting only the distinct ones).

The product of its (nonzero) digits is 8748, while the sum is 36.

The spelling of 21313991061 in words is "twenty-one billion, three hundred thirteen million, nine hundred ninety-one thousand, sixty-one".