20669401 has 2 divisors, whose sum is σ = 20669402. Its totient is φ = 20669400.

The previous prime is 20669393. The next prime is 20669413. The reversal of 20669401 is 10496602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11397376 + 9272025 = 3376^2 + 3045^2 .

It is a cyclic number.

It is not a de Polignac number, because 20669401 - 2³ = 20669393 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20669401.

It is not a weakly prime, because it can be changed into another prime (20669101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10334700 + 10334701.

It is an arithmetic number, because the mean of its divisors is an integer number (10334701).

Almost surely, 2^20669401 is an apocalyptic number.

It is an amenable number.

20669401 is a deficient number, since it is larger than the sum of its proper divisors (1).

20669401 is an equidigital number, since it uses as much as digits as its factorization.

20669401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 20669401 is about 4546.3612922864. The cubic root of 20669401 is about 274.4369792165.

The spelling of 20669401 in words is "twenty million, six hundred sixty-nine thousand, four hundred one".