1661632231 has 8 divisors (see below), whose sum is σ = 1900471680. Its totient is φ = 1423158648.

The previous prime is 1661632199. The next prime is 1661632243. The reversal of 1661632231 is 1322361661.

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 1661632231 - 2⁵ = 1661632199 is a prime.

It is a super-2 number, since 2×1661632231² = 5522043342196074722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1661632193 and 1661632202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661632261) 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, 81661 + ... + 99958.

It is an arithmetic number, because the mean of its divisors is an integer number (237558960).

Almost surely, 2^1661632231 is an apocalyptic number.

1661632231 is a deficient number, since it is larger than the sum of its proper divisors (238839449).

1661632231 is a wasteful number, since it uses less digits than its factorization.

1661632231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182933.

The product of its digits is 7776, while the sum is 31.

The square root of 1661632231 is about 40763.1234205624. The cubic root of 1661632231 is about 1184.4361007559.

Adding to 1661632231 its reverse (1322361661), we get a palindrome (2983993892).

The spelling of 1661632231 in words is "one billion, six hundred sixty-one million, six hundred thirty-two thousand, two hundred thirty-one".