210100661 has 8 divisors (see below), whose sum is σ = 212335200. Its totient is φ = 207871920.

The previous prime is 210100633. The next prime is 210100663. The reversal of 210100661 is 166001012.

It is a happy number.

210100661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 210100661 - 2²² = 205906357 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210100663) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 136466 + ... + 137996.

It is an arithmetic number, because the mean of its divisors is an integer number (26541900).

Almost surely, 2^210100661 is an apocalyptic number.

It is an amenable number.

210100661 is a deficient number, since it is larger than the sum of its proper divisors (2234539).

210100661 is a wasteful number, since it uses less digits than its factorization.

210100661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2899.

The product of its (nonzero) digits is 72, while the sum is 17.

The square root of 210100661 is about 14494.8494645512. The cubic root of 210100661 is about 594.4871517134.

Adding to 210100661 its reverse (166001012), we get a palindrome (376101673).

The spelling of 210100661 in words is "two hundred ten million, one hundred thousand, six hundred sixty-one".