21661042100503 has 8 divisors (see below), whose sum is σ = 23396496516848. Its totient is φ = 19935476313984.

The previous prime is 21661042100501. The next prime is 21661042100527. The reversal of 21661042100503 is 30500124016612.

It is a happy number.

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 21661042100503 - 2¹ = 21661042100501 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21661042100501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2472152901 + ... + 2472161662.

It is an arithmetic number, because the mean of its divisors is an integer number (2924562064606).

Almost surely, 2^{21661042100503} is an apocalyptic number.

21661042100503 is a deficient number, since it is larger than the sum of its proper divisors (1735454416345).

21661042100503 is a wasteful number, since it uses less digits than its factorization.

21661042100503 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4944314913.

The product of its (nonzero) digits is 8640, while the sum is 31.

The spelling of 21661042100503 in words is "twenty-one trillion, six hundred sixty-one billion, forty-two million, one hundred thousand, five hundred three".