21234153777 has 4 divisors (see below), whose sum is σ = 28312205040. Its totient is φ = 14156102516.

The previous prime is 21234153769. The next prime is 21234153791. The reversal of 21234153777 is 77735143212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21234153777 - 2³ = 21234153769 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21234153727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3539025627 + ... + 3539025632.

It is an arithmetic number, because the mean of its divisors is an integer number (7078051260).

Almost surely, 2^21234153777 is an apocalyptic number.

It is an amenable number.

21234153777 is a deficient number, since it is larger than the sum of its proper divisors (7078051263).

21234153777 is an equidigital number, since it uses as much as digits as its factorization.

21234153777 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7078051262.

The product of its digits is 246960, while the sum is 42.

Adding to 21234153777 its reverse (77735143212), we get a palindrome (98969296989).

The spelling of 21234153777 in words is "twenty-one billion, two hundred thirty-four million, one hundred fifty-three thousand, seven hundred seventy-seven".