820006887391 has 2 divisors, whose sum is σ = 820006887392. Its totient is φ = 820006887390.

The previous prime is 820006887341. The next prime is 820006887419. The reversal of 820006887391 is 193788600028.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 820006887391 - 2²³ = 819998498783 is a prime.

It is a super-2 number, since 2×820006887391² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (820006887331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410003443695 + 410003443696.

It is an arithmetic number, because the mean of its divisors is an integer number (410003443696).

Almost surely, 2^820006887391 is an apocalyptic number.

820006887391 is a deficient number, since it is larger than the sum of its proper divisors (1).

820006887391 is an equidigital number, since it uses as much as digits as its factorization.

820006887391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1161216, while the sum is 52.

The spelling of 820006887391 in words is "eight hundred twenty billion, six million, eight hundred eighty-seven thousand, three hundred ninety-one".