20687122 has 4 divisors (see below), whose sum is σ = 31030686. Its totient is φ = 10343560.

The previous prime is 20687087. The next prime is 20687129. The reversal of 20687122 is 22178602.

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

It can be written as a sum of positive squares in only one way, i.e., 20061441 + 625681 = 4479^2 + 791^2 .

It is not an unprimeable number, because it can be changed into a prime (20687129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5171779 + ... + 5171782.

Almost surely, 2^20687122 is an apocalyptic number.

20687122 is a deficient number, since it is larger than the sum of its proper divisors (10343564).

20687122 is a wasteful number, since it uses less digits than its factorization.

20687122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10343563.

The product of its (nonzero) digits is 2688, while the sum is 28.

The square root of 20687122 is about 4548.3097959572. The cubic root of 20687122 is about 274.5153867219.

The spelling of 20687122 in words is "twenty million, six hundred eighty-seven thousand, one hundred twenty-two".