816094951581 has 64 divisors (see below), whose sum is σ = 1377979828736. Its totient is φ = 418056422400.

The previous prime is 816094951561. The next prime is 816094951589. The reversal of 816094951581 is 185159490618.

It is not a de Polignac number, because 816094951581 - 2¹⁸ = 816094689437 is a prime.

It is a super-2 number, since 2×816094951581² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (816094951589) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 5389971 + ... + 5539311.

It is an arithmetic number, because the mean of its divisors is an integer number (21530934824).

Almost surely, 2^816094951581 is an apocalyptic number.

It is an amenable number.

816094951581 is a deficient number, since it is larger than the sum of its proper divisors (561884877155).

816094951581 is a wasteful number, since it uses less digits than its factorization.

816094951581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149942.

The product of its (nonzero) digits is 3110400, while the sum is 57.

The spelling of 816094951581 in words is "eight hundred sixteen billion, ninety-four million, nine hundred fifty-one thousand, five hundred eighty-one".