20454557 has 2 divisors, whose sum is σ = 20454558. Its totient is φ = 20454556.

The previous prime is 20454547. The next prime is 20454559. The reversal of 20454557 is 75545402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16370116 + 4084441 = 4046^2 + 2021^2 .

It is a cyclic number.

It is not a de Polignac number, because 20454557 - 2¹⁶ = 20389021 is a prime.

Together with 20454559, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20454559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10227278 + 10227279.

It is an arithmetic number, because the mean of its divisors is an integer number (10227279).

Almost surely, 2^20454557 is an apocalyptic number.

It is an amenable number.

20454557 is a deficient number, since it is larger than the sum of its proper divisors (1).

20454557 is an equidigital number, since it uses as much as digits as its factorization.

20454557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 28000, while the sum is 32.

The square root of 20454557 is about 4522.6714450643. The cubic root of 20454557 is about 273.4828052517.

Adding to 20454557 its reverse (75545402), we get a palindrome (95999959).

The spelling of 20454557 in words is "twenty million, four hundred fifty-four thousand, five hundred fifty-seven".