20721319131 has 8 divisors (see below), whose sum is σ = 27630876240. Its totient is φ = 13812987392.

The previous prime is 20721319127. The next prime is 20721319133. The reversal of 20721319131 is 13191312702.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20721319131 - 2² = 20721319127 is a prime.

It is a super-2 number, since 2×20721319131² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20721319133) 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 7 ways as a sum of consecutive naturals, for example, 266130 + ... + 335063.

It is an arithmetic number, because the mean of its divisors is an integer number (3453859530).

Almost surely, 2^20721319131 is an apocalyptic number.

20721319131 is a deficient number, since it is larger than the sum of its proper divisors (6909557109).

20721319131 is a wasteful number, since it uses less digits than its factorization.

20721319131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 612685.

The product of its (nonzero) digits is 2268, while the sum is 30.

The spelling of 20721319131 in words is "twenty billion, seven hundred twenty-one million, three hundred nineteen thousand, one hundred thirty-one".