20722154 has 4 divisors (see below), whose sum is σ = 31083234. Its totient is φ = 10361076.

The previous prime is 20722129. The next prime is 20722171. The reversal of 20722154 is 45122702.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 45122702 = 2 ⋅22561351.

It can be written as a sum of positive squares in only one way, i.e., 14645929 + 6076225 = 3827^2 + 2465^2 .

It is a Curzon number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 5180537 + ... + 5180540.

Almost surely, 2^20722154 is an apocalyptic number.

20722154 is a deficient number, since it is larger than the sum of its proper divisors (10361080).

20722154 is a wasteful number, since it uses less digits than its factorization.

20722154 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10361079.

The product of its (nonzero) digits is 1120, while the sum is 23.

The square root of 20722154 is about 4552.1592678640. The cubic root of 20722154 is about 274.6702560119.

Adding to 20722154 its reverse (45122702), we get a palindrome (65844856).

The spelling of 20722154 in words is "twenty million, seven hundred twenty-two thousand, one hundred fifty-four".