20404157 has 16 divisors (see below), whose sum is σ = 22306560. Its totient is φ = 18600192.

The previous prime is 20404133. The next prime is 20404159. The reversal of 20404157 is 75140402.

It is a cyclic number.

It is not a de Polignac number, because 20404157 - 2⁶ = 20404093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20404159) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 65033 + ... + 65345.

It is an arithmetic number, because the mean of its divisors is an integer number (1394160).

Almost surely, 2^20404157 is an apocalyptic number.

It is an amenable number.

20404157 is a deficient number, since it is larger than the sum of its proper divisors (1902403).

20404157 is a wasteful number, since it uses less digits than its factorization.

20404157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 452.

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

The square root of 20404157 is about 4517.0960804481. The cubic root of 20404157 is about 273.2580000933.

Adding to 20404157 its reverse (75140402), we get a palindrome (95544559).

The spelling of 20404157 in words is "twenty million, four hundred four thousand, one hundred fifty-seven".