21661041661034 has 16 divisors (see below), whose sum is σ = 32536282165728. Its totient is φ = 10815622377552.

The previous prime is 21661041660901. The next prime is 21661041661043. The reversal of 21661041661034 is 43016614016612.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21661041660982 and 21661041661000.

It is an unprimeable number.

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, 3325469 + ... + 7374335.

It is an arithmetic number, because the mean of its divisors is an integer number (2033517635358).

Almost surely, 2^{21661041661034} is an apocalyptic number.

21661041661034 is a deficient number, since it is larger than the sum of its proper divisors (10875240504694).

21661041661034 is a wasteful number, since it uses less digits than its factorization.

21661041661034 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4052549.

The product of its (nonzero) digits is 124416, while the sum is 41.

Adding to 21661041661034 its reverse (43016614016612), we get a palindrome (64677655677646).

The spelling of 21661041661034 in words is "twenty-one trillion, six hundred sixty-one billion, forty-one million, six hundred sixty-one thousand, thirty-four".