21153776234 has 16 divisors (see below), whose sum is σ = 32593840776. Its totient is φ = 10289260800.

The previous prime is 21153776233. The next prime is 21153776239. The reversal of 21153776234 is 43267735112.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 19195271209 + 1958505025 = 138547^2 + 44255^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21153776191 and 21153776200.

It is not an unprimeable number, because it can be changed into a prime (21153776233) 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, 479174 + ... + 521454.

Almost surely, 2^21153776234 is an apocalyptic number.

21153776234 is a deficient number, since it is larger than the sum of its proper divisors (11440064542).

21153776234 is a wasteful number, since it uses less digits than its factorization.

21153776234 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49081.

The product of its digits is 211680, while the sum is 41.

The spelling of 21153776234 in words is "twenty-one billion, one hundred fifty-three million, seven hundred seventy-six thousand, two hundred thirty-four".