661001606 has 8 divisors (see below), whose sum is σ = 991927704. Its totient is φ = 330359040.

The previous prime is 661001597. The next prime is 661001609. The reversal of 661001606 is 606100166.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661001609) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64955 + ... + 74438.

It is an arithmetic number, because the mean of its divisors is an integer number (123990963).

Almost surely, 2^661001606 is an apocalyptic number.

661001606 is a deficient number, since it is larger than the sum of its proper divisors (330926098).

661001606 is a wasteful number, since it uses less digits than its factorization.

661001606 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141766.

The product of its (nonzero) digits is 1296, while the sum is 26.

The square root of 661001606 is about 25709.9514974261. The cubic root of 661001606 is about 871.0989793590.

It can be divided in two parts, 66100160 and 6, that added together give a palindrome (66100166).

The spelling of 661001606 in words is "six hundred sixty-one million, one thousand, six hundred six".