20553155 has 32 divisors (see below), whose sum is σ = 30658560. Its totient is φ = 12908160.

The previous prime is 20553139. The next prime is 20553179. The reversal of 20553155 is 55135502.

It is not a de Polignac number, because 20553155 - 2⁴ = 20553139 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20117 + ... + 21113.

It is an arithmetic number, because the mean of its divisors is an integer number (958080).

Almost surely, 2^20553155 is an apocalyptic number.

20553155 is a deficient number, since it is larger than the sum of its proper divisors (10105405).

20553155 is a wasteful number, since it uses less digits than its factorization.

20553155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1059.

The product of its (nonzero) digits is 3750, while the sum is 26.

The square root of 20553155 is about 4533.5587566502. The cubic root of 20553155 is about 273.9215281348.

Adding to 20553155 its reverse (55135502), we get a palindrome (75688657).

The spelling of 20553155 in words is "twenty million, five hundred fifty-three thousand, one hundred fifty-five".