661432101 has 24 divisors (see below), whose sum is σ = 974824032. Its totient is φ = 398613600.

The previous prime is 661432099. The next prime is 661432117. The reversal of 661432101 is 101234166.

It is not a de Polignac number, because 661432101 - 2¹ = 661432099 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661432201) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 60670 + ... + 70736.

It is an arithmetic number, because the mean of its divisors is an integer number (40617668).

Almost surely, 2^661432101 is an apocalyptic number.

It is an amenable number.

661432101 is a deficient number, since it is larger than the sum of its proper divisors (313391931).

661432101 is a wasteful number, since it uses less digits than its factorization.

661432101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10273 (or 10262 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 661432101 is about 25718.3222819841. The cubic root of 661432101 is about 871.2880471670.

Adding to 661432101 its reverse (101234166), we get a palindrome (762666267).

The spelling of 661432101 in words is "six hundred sixty-one million, four hundred thirty-two thousand, one hundred one".