431011661 has 4 divisors (see below), whose sum is σ = 441035232. Its totient is φ = 420988092.

The previous prime is 431011657. The next prime is 431011703. The reversal of 431011661 is 166110134.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 431011661 - 2² = 431011657 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (431017661) 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, 5011721 + ... + 5011806.

It is an arithmetic number, because the mean of its divisors is an integer number (110258808).

Almost surely, 2^431011661 is an apocalyptic number.

It is an amenable number.

431011661 is a deficient number, since it is larger than the sum of its proper divisors (10023571).

431011661 is a wasteful number, since it uses less digits than its factorization.

431011661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10023570.

The product of its (nonzero) digits is 432, while the sum is 23.

The square root of 431011661 is about 20760.8203354299. The cubic root of 431011661 is about 755.3756947795.

Adding to 431011661 its reverse (166110134), we get a palindrome (597121795).

The spelling of 431011661 in words is "four hundred thirty-one million, eleven thousand, six hundred sixty-one".