21170452155 has 32 divisors (see below), whose sum is σ = 36139074048. Its totient is φ = 10545600000.

The previous prime is 21170452117. The next prime is 21170452159. The reversal of 21170452155 is 55125407112.

It is not a de Polignac number, because 21170452155 - 2⁷ = 21170452027 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21170452159) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 283471 + ... + 350280.

It is an arithmetic number, because the mean of its divisors is an integer number (1129346064).

Almost surely, 2^21170452155 is an apocalyptic number.

21170452155 is a deficient number, since it is larger than the sum of its proper divisors (14968621893).

21170452155 is a wasteful number, since it uses less digits than its factorization.

21170452155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 633907.

The product of its (nonzero) digits is 14000, while the sum is 33.

Adding to 21170452155 its reverse (55125407112), we get a palindrome (76295859267).

The spelling of 21170452155 in words is "twenty-one billion, one hundred seventy million, four hundred fifty-two thousand, one hundred fifty-five".