661862958 has 16 divisors (see below), whose sum is σ = 1366427136. Its totient is φ = 213504120.

The previous prime is 661862953. The next prime is 661862963. The reversal of 661862958 is 859268166.

It is an interprime number because it is at equal distance from previous prime (661862953) and next prime (661862963).

It is a self number, because there is not a number n which added to its sum of digits gives 661862958.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661862951) 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 7 ways as a sum of consecutive naturals, for example, 1779016 + ... + 1779387.

It is an arithmetic number, because the mean of its divisors is an integer number (85401696).

Almost surely, 2^661862958 is an apocalyptic number.

661862958 is an abundant number, since it is smaller than the sum of its proper divisors (704564178).

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

661862958 is a wasteful number, since it uses less digits than its factorization.

661862958 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3558439.

The product of its digits is 1244160, while the sum is 51.

The square root of 661862958 is about 25726.6973784044. The cubic root of 661862958 is about 871.4771918381.

The spelling of 661862958 in words is "six hundred sixty-one million, eight hundred sixty-two thousand, nine hundred fifty-eight".