21161777153 has 16 divisors (see below), whose sum is σ = 23434012800. Its totient is φ = 18949265280.

The previous prime is 21161777113. The next prime is 21161777171. The reversal of 21161777153 is 35177716112.

It is not a de Polignac number, because 21161777153 - 2⁸ = 21161776897 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21161777153.

It is not an unprimeable number, because it can be changed into a prime (21161777113) 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, 216383 + ... + 298571.

It is an arithmetic number, because the mean of its divisors is an integer number (1464625800).

Almost surely, 2^21161777153 is an apocalyptic number.

It is an amenable number.

21161777153 is a deficient number, since it is larger than the sum of its proper divisors (2272235647).

21161777153 is a wasteful number, since it uses less digits than its factorization.

21161777153 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82552.

The product of its digits is 61740, while the sum is 41.

The spelling of 21161777153 in words is "twenty-one billion, one hundred sixty-one million, seven hundred seventy-seven thousand, one hundred fifty-three".