612000000081891 has 12 divisors (see below), whose sum is σ = 889293413294832. Its totient is φ = 405556886280816.

The previous prime is 612000000081871. The next prime is 612000000081901. The reversal of 612000000081891 is 198180000000216.

It is not a de Polignac number, because 612000000081891 - 2¹¹ = 612000000079843 is a prime.

It is a super-2 number, since 2×612000000081891² (a number of 30 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (612000000081851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 203592812896 + ... + 203592815901.

It is an arithmetic number, because the mean of its divisors is an integer number (74107784441236).

Almost surely, 2^{612000000081891} is an apocalyptic number.

612000000081891 is a deficient number, since it is larger than the sum of its proper divisors (277293413212941).

612000000081891 is a wasteful number, since it uses less digits than its factorization.

612000000081891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 407185628970 (or 407185628967 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 36.

The spelling of 612000000081891 in words is "six hundred twelve trillion, eighty-one thousand, eight hundred ninety-one".