20769251 has 2 divisors, whose sum is σ = 20769252. Its totient is φ = 20769250.

The previous prime is 20769233. The next prime is 20769271. The reversal of 20769251 is 15296702.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20769251 - 2¹⁸ = 20507107 is a prime.

It is not a weakly prime, because it can be changed into another prime (20769211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10384625 + 10384626.

It is an arithmetic number, because the mean of its divisors is an integer number (10384626).

Almost surely, 2^20769251 is an apocalyptic number.

20769251 is a deficient number, since it is larger than the sum of its proper divisors (1).

20769251 is an equidigital number, since it uses as much as digits as its factorization.

20769251 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7560, while the sum is 32.

The square root of 20769251 is about 4557.3293714631. The cubic root of 20769251 is about 274.8781873728.

The spelling of 20769251 in words is "twenty million, seven hundred sixty-nine thousand, two hundred fifty-one".