21112154507 has 2 divisors, whose sum is σ = 21112154508. Its totient is φ = 21112154506.

The previous prime is 21112154489. The next prime is 21112154521. The reversal of 21112154507 is 70545121112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21112154507 - 2⁶ = 21112154443 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21112154507.

It is not a weakly prime, because it can be changed into another prime (21112154587) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556077253 + 10556077254.

It is an arithmetic number, because the mean of its divisors is an integer number (10556077254).

Almost surely, 2^21112154507 is an apocalyptic number.

21112154507 is a deficient number, since it is larger than the sum of its proper divisors (1).

21112154507 is an equidigital number, since it uses as much as digits as its factorization.

21112154507 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2800, while the sum is 29.

Adding to 21112154507 its reverse (70545121112), we get a palindrome (91657275619).

The spelling of 21112154507 in words is "twenty-one billion, one hundred twelve million, one hundred fifty-four thousand, five hundred seven".