21123115601 has 8 divisors (see below), whose sum is σ = 24178020480. Its totient is φ = 18077539968.

The previous prime is 21123115591. The next prime is 21123115697. The reversal of 21123115601 is 10651132112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21123115601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21123115001) 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, 2327456 + ... + 2336513.

It is an arithmetic number, because the mean of its divisors is an integer number (3022252560).

Almost surely, 2^21123115601 is an apocalyptic number.

It is an amenable number.

21123115601 is a deficient number, since it is larger than the sum of its proper divisors (3054904879).

21123115601 is an equidigital number, since it uses as much as digits as its factorization.

21123115601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4664623.

The product of its (nonzero) digits is 360, while the sum is 23.

Adding to 21123115601 its reverse (10651132112), we get a palindrome (31774247713).

The spelling of 21123115601 in words is "twenty-one billion, one hundred twenty-three million, one hundred fifteen thousand, six hundred one".