21661054406233 has 8 divisors (see below), whose sum is σ = 23632390874016. Its totient is φ = 19690076222400.

The previous prime is 21661054406231. The next prime is 21661054406239. The reversal of 21661054406233 is 33260445016612.

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 21661054406233 - 2¹ = 21661054406231 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21661054406233.

It is not an unprimeable number, because it can be changed into a prime (21661054406231) 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, 89444563 + ... + 89686408.

It is an arithmetic number, because the mean of its divisors is an integer number (2954048859252).

Almost surely, 2^{21661054406233} is an apocalyptic number.

It is an amenable number.

21661054406233 is a deficient number, since it is larger than the sum of its proper divisors (1971336467783).

21661054406233 is a wasteful number, since it uses less digits than its factorization.

21661054406233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179141975.

The product of its (nonzero) digits is 622080, while the sum is 43.

The spelling of 21661054406233 in words is "twenty-one trillion, six hundred sixty-one billion, fifty-four million, four hundred six thousand, two hundred thirty-three".