20619601 has 2 divisors, whose sum is σ = 20619602. Its totient is φ = 20619600.

The previous prime is 20619587. The next prime is 20619629. The reversal of 20619601 is 10691602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18662400 + 1957201 = 4320^2 + 1399^2 .

It is a cyclic number.

It is not a de Polignac number, because 20619601 - 2⁹ = 20619089 is a prime.

It is not a weakly prime, because it can be changed into another prime (20619671) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10309800 + 10309801.

It is an arithmetic number, because the mean of its divisors is an integer number (10309801).

Almost surely, 2^20619601 is an apocalyptic number.

It is an amenable number.

20619601 is a deficient number, since it is larger than the sum of its proper divisors (1).

20619601 is an equidigital number, since it uses as much as digits as its factorization.

20619601 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 20619601 is about 4540.8810819047. The cubic root of 20619601 is about 274.2163962642.

The spelling of 20619601 in words is "twenty million, six hundred nineteen thousand, six hundred one".