21052523155 has 16 divisors (see below), whose sum is σ = 26776854720. Its totient is φ = 15834857472.

The previous prime is 21052523153. The next prime is 21052523197. The reversal of 21052523155 is 55132525012.

It is a cyclic number.

It is not a de Polignac number, because 21052523155 - 2¹ = 21052523153 is a prime.

It is a super-2 number, since 2×21052523155² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21052523153) 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, 45870 + ... + 210259.

It is an arithmetic number, because the mean of its divisors is an integer number (1673553420).

Almost surely, 2^21052523155 is an apocalyptic number.

21052523155 is a deficient number, since it is larger than the sum of its proper divisors (5724331565).

21052523155 is a wasteful number, since it uses less digits than its factorization.

21052523155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 257118.

The product of its (nonzero) digits is 15000, while the sum is 31.

The spelling of 21052523155 in words is "twenty-one billion, fifty-two million, five hundred twenty-three thousand, one hundred fifty-five".