21145002305 has 32 divisors (see below), whose sum is σ = 30719969280. Its totient is φ = 13639726080.

The previous prime is 21145002301. The next prime is 21145002311. The reversal of 21145002305 is 50320054112.

It is not a de Polignac number, because 21145002305 - 2² = 21145002301 is a prime.

It is a super-2 number, since 2×21145002305² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21145002301) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1366160 + ... + 1381550.

It is an arithmetic number, because the mean of its divisors is an integer number (959999040).

Almost surely, 2^21145002305 is an apocalyptic number.

It is an amenable number.

21145002305 is a deficient number, since it is larger than the sum of its proper divisors (9574966975).

21145002305 is a wasteful number, since it uses less digits than its factorization.

21145002305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17729.

The product of its (nonzero) digits is 1200, while the sum is 23.

Adding to 21145002305 its reverse (50320054112), we get a palindrome (71465056417).

The spelling of 21145002305 in words is "twenty-one billion, one hundred forty-five million, two thousand, three hundred five".