20649953 has 2 divisors, whose sum is σ = 20649954. Its totient is φ = 20649952.

The previous prime is 20649949. The next prime is 20649973. The reversal of 20649953 is 35994602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16418704 + 4231249 = 4052^2 + 2057^2 .

It is a cyclic number.

It is not a de Polignac number, because 20649953 - 2² = 20649949 is a prime.

It is not a weakly prime, because it can be changed into another prime (20649973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10324976 + 10324977.

It is an arithmetic number, because the mean of its divisors is an integer number (10324977).

Almost surely, 2^20649953 is an apocalyptic number.

It is an amenable number.

20649953 is a deficient number, since it is larger than the sum of its proper divisors (1).

20649953 is an equidigital number, since it uses as much as digits as its factorization.

20649953 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 58320, while the sum is 38.

The square root of 20649953 is about 4544.2219356013. The cubic root of 20649953 is about 274.3508789113.

The spelling of 20649953 in words is "twenty million, six hundred forty-nine thousand, nine hundred fifty-three".