20361553 has 2 divisors, whose sum is σ = 20361554. Its totient is φ = 20361552.

The previous prime is 20361547. The next prime is 20361557. The reversal of 20361553 is 35516302.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11881809 + 8479744 = 3447^2 + 2912^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20361553 is a prime.

It is equal to p_1292065 and since 20361553 and 1292065 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (20361557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10180776 + 10180777.

It is an arithmetic number, because the mean of its divisors is an integer number (10180777).

Almost surely, 2^20361553 is an apocalyptic number.

It is an amenable number.

20361553 is a deficient number, since it is larger than the sum of its proper divisors (1).

20361553 is an equidigital number, since it uses as much as digits as its factorization.

20361553 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2700, while the sum is 25.

The square root of 20361553 is about 4512.3777545768. The cubic root of 20361553 is about 273.0676794637.

Adding to 20361553 its reverse (35516302), we get a palindrome (55877855).

The spelling of 20361553 in words is "twenty million, three hundred sixty-one thousand, five hundred fifty-three".