20310299981 has 4 divisors (see below), whose sum is σ = 20311025952. Its totient is φ = 20309574012.

The previous prime is 20310299941. The next prime is 20310299987. The reversal of 20310299981 is 18999201302.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20310299981 - 2⁶ = 20310299917 is a prime.

It is a super-2 number, since 2×20310299981² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20310299987) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 319265 + ... + 377558.

It is an arithmetic number, because the mean of its divisors is an integer number (5077756488).

Almost surely, 2^20310299981 is an apocalyptic number.

It is an amenable number.

20310299981 is a deficient number, since it is larger than the sum of its proper divisors (725971).

20310299981 is an equidigital number, since it uses as much as digits as its factorization.

20310299981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 725970.

The product of its (nonzero) digits is 69984, while the sum is 44.

The spelling of 20310299981 in words is "twenty billion, three hundred ten million, two hundred ninety-nine thousand, nine hundred eighty-one".