21154152243 has 16 divisors (see below), whose sum is σ = 32240630016. Its totient is φ = 12085937760.

The previous prime is 21154152233. The next prime is 21154152259. The reversal of 21154152243 is 34225145112.

It is not a de Polignac number, because 21154152243 - 2⁶ = 21154152179 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21154152243.

It is not an unprimeable number, because it can be changed into a prime (21154152233) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 35428 + ... + 208718.

It is an arithmetic number, because the mean of its divisors is an integer number (2015039376).

Almost surely, 2^21154152243 is an apocalyptic number.

21154152243 is a deficient number, since it is larger than the sum of its proper divisors (11086477773).

21154152243 is a wasteful number, since it uses less digits than its factorization.

21154152243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179114.

The product of its digits is 9600, while the sum is 30.

Adding to 21154152243 its reverse (34225145112), we get a palindrome (55379297355).

The spelling of 21154152243 in words is "twenty-one billion, one hundred fifty-four million, one hundred fifty-two thousand, two hundred forty-three".