661005034520 has 32 divisors (see below), whose sum is σ = 1487344241520. Its totient is φ = 264387273600.

The previous prime is 661005034511. The next prime is 661005034561. The reversal of 661005034520 is 25430500166.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 280559 + ... + 1183521.

Almost surely, 2^661005034520 is an apocalyptic number.

It is an amenable number.

661005034520 is an abundant number, since it is smaller than the sum of its proper divisors (826339207000).

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

661005034520 is a wasteful number, since it uses less digits than its factorization.

661005034520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 921275 (or 921271 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 32.

Adding to 661005034520 its reverse (25430500166), we get a palindrome (686435534686).

The spelling of 661005034520 in words is "six hundred sixty-one billion, five million, thirty-four thousand, five hundred twenty".