661146826 has 4 divisors (see below), whose sum is σ = 991720242. Its totient is φ = 330573412.

The previous prime is 661146797. The next prime is 661146839. The reversal of 661146826 is 628641166.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 589761225 + 71385601 = 24285^2 + 8449^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165286705 + ... + 165286708.

Almost surely, 2^661146826 is an apocalyptic number.

661146826 is a deficient number, since it is larger than the sum of its proper divisors (330573416).

661146826 is a wasteful number, since it uses less digits than its factorization.

661146826 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 330573415.

The product of its digits is 82944, while the sum is 40.

The square root of 661146826 is about 25712.7755405752. The cubic root of 661146826 is about 871.1627672680.

The spelling of 661146826 in words is "six hundred sixty-one million, one hundred forty-six thousand, eight hundred twenty-six".