21123145001 has 8 divisors (see below), whose sum is σ = 24172135680. Its totient is φ = 18082003968.

The previous prime is 21123144983. The next prime is 21123145003. The reversal of 21123145001 is 10054132112.

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

It is a de Polignac number, because none of the positive numbers 2^k-21123145001 is a prime.

It is a super-3 number, since 3×21123145001³ (a number of 32 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (21123145003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1956641 + ... + 1967406.

It is an arithmetic number, because the mean of its divisors is an integer number (3021516960).

Almost surely, 2^21123145001 is an apocalyptic number.

It is an amenable number.

21123145001 is a deficient number, since it is larger than the sum of its proper divisors (3048990679).

21123145001 is an equidigital number, since it uses as much as digits as its factorization.

21123145001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3924823.

The product of its (nonzero) digits is 240, while the sum is 20.

Adding to 21123145001 its reverse (10054132112), we get a palindrome (31177277113).

The spelling of 21123145001 in words is "twenty-one billion, one hundred twenty-three million, one hundred forty-five thousand, one".