1581168226 has 24 divisors (see below), whose sum is σ = 2612806812. Its totient is φ = 717103200.

The previous prime is 1581168223. The next prime is 1581168269. The reversal of 1581168226 is 6228611851.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1560329001 + 20839225 = 39501^2 + 4565^2 .

It is not an unprimeable number, because it can be changed into a prime (1581168223) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 104476 + ... + 118648.

Almost surely, 2^1581168226 is an apocalyptic number.

1581168226 is a deficient number, since it is larger than the sum of its proper divisors (1031638586).

1581168226 is a wasteful number, since it uses less digits than its factorization.

1581168226 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14658 (or 14647 counting only the distinct ones).

The product of its digits is 46080, while the sum is 40.

The square root of 1581168226 is about 39763.9060707069. The cubic root of 1581168226 is about 1165.0002704046. Note that the first 3 decimals are identical.

The spelling of 1581168226 in words is "one billion, five hundred eighty-one million, one hundred sixty-eight thousand, two hundred twenty-six".