661449513 has 8 divisors (see below), whose sum is σ = 891842400. Its totient is φ = 436011488.

The previous prime is 661449473. The next prime is 661449539. The reversal of 661449513 is 315944166.

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 661449513 - 2¹⁸ = 661187369 is a prime.

It is not an unprimeable number, because it can be changed into a prime (661449013) 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, 1238403 + ... + 1238936.

It is an arithmetic number, because the mean of its divisors is an integer number (111480300).

Almost surely, 2^661449513 is an apocalyptic number.

It is an amenable number.

661449513 is a deficient number, since it is larger than the sum of its proper divisors (230392887).

661449513 is a wasteful number, since it uses less digits than its factorization.

661449513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2477431.

The product of its digits is 77760, while the sum is 39.

The square root of 661449513 is about 25718.6607932839. The cubic root of 661449513 is about 871.2956925647.

It can be divided in two parts, 66144 and 9513, that added together give a palindrome (75657).

The spelling of 661449513 in words is "six hundred sixty-one million, four hundred forty-nine thousand, five hundred thirteen".