816525491 has 2 divisors, whose sum is σ = 816525492. Its totient is φ = 816525490.

The previous prime is 816525401. The next prime is 816525497. The reversal of 816525491 is 194525618.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 816525491 - 2¹⁴ = 816509107 is a prime.

It is not a weakly prime, because it can be changed into another prime (816525497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 408262745 + 408262746.

It is an arithmetic number, because the mean of its divisors is an integer number (408262746).

Almost surely, 2^816525491 is an apocalyptic number.

816525491 is a deficient number, since it is larger than the sum of its proper divisors (1).

816525491 is an equidigital number, since it uses as much as digits as its factorization.

816525491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 86400, while the sum is 41.

The square root of 816525491 is about 28574.9101660880. The cubic root of 816525491 is about 934.6662963110. Note that the first 3 decimals are identical.

The spelling of 816525491 in words is "eight hundred sixteen million, five hundred twenty-five thousand, four hundred ninety-one".