851088691 has 4 divisors (see below), whose sum is σ = 859351792. Its totient is φ = 842825592.

The previous prime is 851088617. The next prime is 851088703. The reversal of 851088691 is 196880158.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 196880158 = 2 ⋅98440079.

It is a cyclic number.

It is not a de Polignac number, because 851088691 - 2¹³ = 851080499 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (851088991) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4131396 + ... + 4131601.

It is an arithmetic number, because the mean of its divisors is an integer number (214837948).

Almost surely, 2^851088691 is an apocalyptic number.

851088691 is a deficient number, since it is larger than the sum of its proper divisors (8263101).

851088691 is a wasteful number, since it uses less digits than its factorization.

851088691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8263100.

The product of its (nonzero) digits is 138240, while the sum is 46.

The square root of 851088691 is about 29173.4243961863. The cubic root of 851088691 is about 947.6724891170.

The spelling of 851088691 in words is "eight hundred fifty-one million, eighty-eight thousand, six hundred ninety-one".