21406713993 has 32 divisors (see below), whose sum is σ = 36259941120. Its totient is φ = 12227086080.

The previous prime is 21406713989. The next prime is 21406714001. The reversal of 21406713993 is 39931760412.

21406713993 is a `hidden beast` number, since 21 + 406 + 7 + 139 + 93 = 666.

It is not a de Polignac number, because 21406713993 - 2² = 21406713989 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21406713193) 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 31 ways as a sum of consecutive naturals, for example, 433383 + ... + 480243.

It is an arithmetic number, because the mean of its divisors is an integer number (1133123160).

Almost surely, 2^21406713993 is an apocalyptic number.

It is an amenable number.

21406713993 is a deficient number, since it is larger than the sum of its proper divisors (14853227127).

21406713993 is a wasteful number, since it uses less digits than its factorization.

21406713993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49294 (or 49288 counting only the distinct ones).

The product of its (nonzero) digits is 244944, while the sum is 45.

The spelling of 21406713993 in words is "twenty-one billion, four hundred six million, seven hundred thirteen thousand, nine hundred ninety-three".