20011219831 has 2 divisors, whose sum is σ = 20011219832. Its totient is φ = 20011219830.

The previous prime is 20011219829. The next prime is 20011219847. The reversal of 20011219831 is 13891211002.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20011219831 - 2¹ = 20011219829 is a prime.

It is a super-2 number, since 2×20011219831² (a number of 21 digits) contains 22 as substring.

Together with 20011219829, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 20011219831.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20011219871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10005609915 + 10005609916.

It is an arithmetic number, because the mean of its divisors is an integer number (10005609916).

Almost surely, 2^20011219831 is an apocalyptic number.

20011219831 is a deficient number, since it is larger than the sum of its proper divisors (1).

20011219831 is an equidigital number, since it uses as much as digits as its factorization.

20011219831 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 28.

The spelling of 20011219831 in words is "twenty billion, eleven million, two hundred nineteen thousand, eight hundred thirty-one".