641166426 has 12 divisors (see below), whose sum is σ = 1389193962. Its totient is φ = 213722136.

The previous prime is 641166391. The next prime is 641166437. The reversal of 641166426 is 624661146.

641166426 is a `hidden beast` number, since 6 + 4 + 1 + 1 + 6 + 642 + 6 = 666.

It can be written as a sum of positive squares in only one way, i.e., 449482401 + 191684025 = 21201^2 + 13845^2 .

It is a super-3 number, since 3×641166426³ (a number of 27 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 17810161 + ... + 17810196.

Almost surely, 2^641166426 is an apocalyptic number.

641166426 is an abundant number, since it is smaller than the sum of its proper divisors (748027536).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

641166426 is a wasteful number, since it uses less digits than its factorization.

641166426 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35620365 (or 35620362 counting only the distinct ones).

The product of its digits is 41472, while the sum is 36.

The square root of 641166426 is about 25321.2643049276. The cubic root of 641166426 is about 862.2970975767.

The spelling of 641166426 in words is "six hundred forty-one million, one hundred sixty-six thousand, four hundred twenty-six".