20726649 has 12 divisors (see below), whose sum is σ = 30219696. Its totient is φ = 13687992.

The previous prime is 20726647. The next prime is 20726653. The reversal of 20726649 is 94662702.

It is a happy number.

20726649 is a `hidden beast` number, since 2 + 0 + 7 + 2 + 6 + 649 = 666.

It is not a de Polignac number, because 20726649 - 2¹ = 20726647 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20726647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9799 + ... + 11724.

It is an arithmetic number, because the mean of its divisors is an integer number (2518308).

Almost surely, 2^20726649 is an apocalyptic number.

It is an amenable number.

20726649 is a deficient number, since it is larger than the sum of its proper divisors (9493047).

20726649 is a wasteful number, since it uses less digits than its factorization.

20726649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21636 (or 21633 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 36.

The square root of 20726649 is about 4552.6529628339. The cubic root of 20726649 is about 274.6901148473.

The spelling of 20726649 in words is "twenty million, seven hundred twenty-six thousand, six hundred forty-nine".