20040551 has 2 divisors, whose sum is σ = 20040552. Its totient is φ = 20040550.

The previous prime is 20040547. The next prime is 20040557. The reversal of 20040551 is 15504002.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20040551 - 2² = 20040547 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20040557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10020275 + 10020276.

It is an arithmetic number, because the mean of its divisors is an integer number (10020276).

Almost surely, 2^20040551 is an apocalyptic number.

20040551 is a deficient number, since it is larger than the sum of its proper divisors (1).

20040551 is an equidigital number, since it uses as much as digits as its factorization.

20040551 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 200, while the sum is 17.

The square root of 20040551 is about 4476.6673988582. The cubic root of 20040551 is about 271.6250917263.

Adding to 20040551 its reverse (15504002), we get a palindrome (35544553).

The spelling of 20040551 in words is "twenty million, forty thousand, five hundred fifty-one".