861055511 has 2 divisors, whose sum is σ = 861055512. Its totient is φ = 861055510.

The previous prime is 861055493. The next prime is 861055561. The reversal of 861055511 is 115550168.

861055511 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-861055511 is a prime.

It is a super-2 number, since 2×861055511² = 1482833186046942242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (861055561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430527755 + 430527756.

It is an arithmetic number, because the mean of its divisors is an integer number (430527756).

Almost surely, 2^861055511 is an apocalyptic number.

861055511 is a deficient number, since it is larger than the sum of its proper divisors (1).

861055511 is an equidigital number, since it uses as much as digits as its factorization.

861055511 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6000, while the sum is 32.

The square root of 861055511 is about 29343.7473919062. The cubic root of 861055511 is about 951.3574356413.

The spelling of 861055511 in words is "eight hundred sixty-one million, fifty-five thousand, five hundred eleven".