661630337 has 4 divisors (see below), whose sum is σ = 679512276. Its totient is φ = 643748400.

The previous prime is 661630283. The next prime is 661630367. The reversal of 661630337 is 733036166.

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

It can be written as a sum of positive squares in 2 ways, for example, as 562448656 + 99181681 = 23716^2 + 9959^2 .

It is a cyclic number.

It is not a de Polignac number, because 661630337 - 2¹² = 661626241 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 661630297 and 661630306.

It is not an unprimeable number, because it can be changed into a prime (661630367) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8940914 + ... + 8940987.

It is an arithmetic number, because the mean of its divisors is an integer number (169878069).

Almost surely, 2^661630337 is an apocalyptic number.

It is an amenable number.

661630337 is a deficient number, since it is larger than the sum of its proper divisors (17881939).

661630337 is a wasteful number, since it uses less digits than its factorization.

661630337 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17881938.

The product of its (nonzero) digits is 40824, while the sum is 35.

The square root of 661630337 is about 25722.1759771603. The cubic root of 661630337 is about 871.3750822558.

The spelling of 661630337 in words is "six hundred sixty-one million, six hundred thirty thousand, three hundred thirty-seven".