661003431 has 8 divisors (see below), whose sum is σ = 961459584. Its totient is φ = 400608120.

The previous prime is 661003411. The next prime is 661003433. The reversal of 661003431 is 134300166.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 661003431 - 2⁹ = 661002919 is a prime.

It is a super-2 number, since 2×661003431² = 873851071587543522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661003433) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10015171 + ... + 10015236.

It is an arithmetic number, because the mean of its divisors is an integer number (120182448).

Almost surely, 2^661003431 is an apocalyptic number.

661003431 is a deficient number, since it is larger than the sum of its proper divisors (300456153).

661003431 is a wasteful number, since it uses less digits than its factorization.

661003431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20030421.

The product of its (nonzero) digits is 1296, while the sum is 24.

The square root of 661003431 is about 25709.9869894950. The cubic root of 661003431 is about 871.0997810485.

Adding to 661003431 its reverse (134300166), we get a palindrome (795303597).

The spelling of 661003431 in words is "six hundred sixty-one million, three thousand, four hundred thirty-one".