20687153 has 4 divisors (see below), whose sum is σ = 20700708. Its totient is φ = 20673600.

The previous prime is 20687141. The next prime is 20687159. The reversal of 20687153 is 35178602.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4631104 + 16056049 = 2152^2 + 4007^2 .

It is a cyclic number.

It is not a de Polignac number, because 20687153 - 2¹² = 20683057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20687159) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4148 + ... + 7653.

It is an arithmetic number, because the mean of its divisors is an integer number (5175177).

Almost surely, 2^20687153 is an apocalyptic number.

It is an amenable number.

20687153 is a deficient number, since it is larger than the sum of its proper divisors (13555).

20687153 is a wasteful number, since it uses less digits than its factorization.

20687153 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13554.

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 20687153 is about 4548.3132038152. The cubic root of 20687153 is about 274.5155238438.

The spelling of 20687153 in words is "twenty million, six hundred eighty-seven thousand, one hundred fifty-three".