661231661046 has 32 divisors (see below), whose sum is σ = 1442824800768. Its totient is φ = 200354127840.

The previous prime is 661231661033. The next prime is 661231661047. The reversal of 661231661046 is 640166132166.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 661231660989 and 661231661007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661231661047) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 227796 + ... + 1172328.

It is an arithmetic number, because the mean of its divisors is an integer number (45088275024).

Almost surely, 2^661231661046 is an apocalyptic number.

661231661046 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

661231661046 is an abundant number, since it is smaller than the sum of its proper divisors (781593139722).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

661231661046 is a wasteful number, since it uses less digits than its factorization.

661231661046 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 955156.

The product of its (nonzero) digits is 186624, while the sum is 42.

The spelling of 661231661046 in words is "six hundred sixty-one billion, two hundred thirty-one million, six hundred sixty-one thousand, forty-six".