21006340131 has 48 divisors (see below), whose sum is σ = 34566696960. Its totient is φ = 11282120640.

The previous prime is 21006340109. The next prime is 21006340141. The reversal of 21006340131 is 13104360012.

It is not a de Polignac number, because 21006340131 - 2⁵ = 21006340099 is a prime.

It is a super-2 number, since 2×21006340131² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 21006340098 and 21006340107.

It is not an unprimeable number, because it can be changed into a prime (21006340141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 325101 + ... + 384321.

It is an arithmetic number, because the mean of its divisors is an integer number (720139520).

Almost surely, 2^21006340131 is an apocalyptic number.

21006340131 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21006340131 is a deficient number, since it is larger than the sum of its proper divisors (13560356829).

21006340131 is a wasteful number, since it uses less digits than its factorization.

21006340131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59384 (or 59377 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 21.

The spelling of 21006340131 in words is "twenty-one billion, six million, three hundred forty thousand, one hundred thirty-one".