20871851411 has 2 divisors, whose sum is σ = 20871851412. Its totient is φ = 20871851410.

The previous prime is 20871851393. The next prime is 20871851417. The reversal of 20871851411 is 11415817802.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20871851411 is a prime.

It is not a weakly prime, because it can be changed into another prime (20871851417) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10435925705 + 10435925706.

It is an arithmetic number, because the mean of its divisors is an integer number (10435925706).

Almost surely, 2^20871851411 is an apocalyptic number.

20871851411 is a deficient number, since it is larger than the sum of its proper divisors (1).

20871851411 is an equidigital number, since it uses as much as digits as its factorization.

20871851411 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17920, while the sum is 38.

The spelling of 20871851411 in words is "twenty billion, eight hundred seventy-one million, eight hundred fifty-one thousand, four hundred eleven".