21661031332124 has 24 divisors (see below), whose sum is σ = 37948510206096. Its totient is φ = 10818606240000.

The previous prime is 21661031332123. The next prime is 21661031332159. The reversal of 21661031332124 is 42123313016612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21661031332123) 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, 12782174 + ... + 14377274.

It is an arithmetic number, because the mean of its divisors is an integer number (1581187925254).

Almost surely, 2^{21661031332124} is an apocalyptic number.

It is an amenable number.

21661031332124 is a deficient number, since it is larger than the sum of its proper divisors (16287478873972).

21661031332124 is a wasteful number, since it uses less digits than its factorization.

21661031332124 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1598837 (or 1598835 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 35.

Adding to 21661031332124 its reverse (42123313016612), we get a palindrome (63784344348736).

The spelling of 21661031332124 in words is "twenty-one trillion, six hundred sixty-one billion, thirty-one million, three hundred thirty-two thousand, one hundred twenty-four".