661400519 has 8 divisors (see below), whose sum is σ = 712639872. Its totient is φ = 610212960.

The previous prime is 661400471. The next prime is 661400527. The reversal of 661400519 is 915004166.

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 661400519 - 2⁸ = 661400263 is a prime.

It is a super-2 number, since 2×661400519² = 874901293066938722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661400549) 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, 15989 + ... + 39729.

It is an arithmetic number, because the mean of its divisors is an integer number (89079984).

Almost surely, 2^661400519 is an apocalyptic number.

661400519 is a deficient number, since it is larger than the sum of its proper divisors (51239353).

661400519 is a wasteful number, since it uses less digits than its factorization.

661400519 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25897.

The product of its (nonzero) digits is 6480, while the sum is 32.

The square root of 661400519 is about 25717.7082765942. The cubic root of 661400519 is about 871.2741795520.

The spelling of 661400519 in words is "six hundred sixty-one million, four hundred thousand, five hundred nineteen".