891894551 has 2 divisors, whose sum is σ = 891894552. Its totient is φ = 891894550.

The previous prime is 891894503. The next prime is 891894557. The reversal of 891894551 is 155498198.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-891894551 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 891894551.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (891894557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 445947275 + 445947276.

It is an arithmetic number, because the mean of its divisors is an integer number (445947276).

Almost surely, 2^891894551 is an apocalyptic number.

891894551 is a deficient number, since it is larger than the sum of its proper divisors (1).

891894551 is an equidigital number, since it uses as much as digits as its factorization.

891894551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 518400, while the sum is 50.

The square root of 891894551 is about 29864.6036471271. The cubic root of 891894551 is about 962.5822230539.

The spelling of 891894551 in words is "eight hundred ninety-one million, eight hundred ninety-four thousand, five hundred fifty-one".