1661862826 has 16 divisors (see below), whose sum is σ = 2685841704. Its totient is φ = 766643904.

The previous prime is 1661862821. The next prime is 1661862827. The reversal of 1661862826 is 6282681661.

It can be written as a sum of positive squares in 4 ways, for example, as 803665801 + 858197025 = 28349^2 + 29295^2 .

It is not an unprimeable number, because it can be changed into a prime (1661862821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 43876 + ... + 72448.

Almost surely, 2^1661862826 is an apocalyptic number.

1661862826 is a deficient number, since it is larger than the sum of its proper divisors (1023978878).

1661862826 is a wasteful number, since it uses less digits than its factorization.

1661862826 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30825.

The product of its digits is 331776, while the sum is 46.

The square root of 1661862826 is about 40765.9517980385. The cubic root of 1661862826 is about 1184.4908887337.

The spelling of 1661862826 in words is "one billion, six hundred sixty-one million, eight hundred sixty-two thousand, eight hundred twenty-six".