661831419 has 4 divisors (see below), whose sum is σ = 882441896. Its totient is φ = 441220944.

The previous prime is 661831411. The next prime is 661831421. The reversal of 661831419 is 914138166.

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

It is not a de Polignac number, because 661831419 - 2³ = 661831411 is a prime.

It is a super-2 number, since 2×661831419² = 876041654351107122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (661831411) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 110305234 + ... + 110305239.

It is an arithmetic number, because the mean of its divisors is an integer number (220610474).

Almost surely, 2^661831419 is an apocalyptic number.

661831419 is a deficient number, since it is larger than the sum of its proper divisors (220610477).

661831419 is a wasteful number, since it uses less digits than its factorization.

661831419 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220610476.

The product of its digits is 31104, while the sum is 39.

The square root of 661831419 is about 25726.0844086309. The cubic root of 661831419 is about 871.4633491156.

The spelling of 661831419 in words is "six hundred sixty-one million, eight hundred thirty-one thousand, four hundred nineteen".