213265600661 has 16 divisors (see below), whose sum is σ = 232315951536. Its totient is φ = 194956886016.

The previous prime is 213265600619. The next prime is 213265600663. The reversal of 213265600661 is 166006562312.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 81264904900 + 132000695761 = 285070^2 + 363319^2 .

It is a cyclic number.

It is not a de Polignac number, because 213265600661 - 2¹⁰ = 213265599637 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213265600663) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 69125 + ... + 656741.

It is an arithmetic number, because the mean of its divisors is an integer number (14519746971).

Almost surely, 2^213265600661 is an apocalyptic number.

It is an amenable number.

213265600661 is a deficient number, since it is larger than the sum of its proper divisors (19050350875).

213265600661 is a wasteful number, since it uses less digits than its factorization.

213265600661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 588248.

The product of its (nonzero) digits is 77760, while the sum is 38.

The spelling of 213265600661 in words is "two hundred thirteen billion, two hundred sixty-five million, six hundred thousand, six hundred sixty-one".