20542751 has 2 divisors, whose sum is σ = 20542752. Its totient is φ = 20542750.

The previous prime is 20542741. The next prime is 20542771. The reversal of 20542751 is 15724502.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20542751 - 2¹⁸ = 20280607 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20542751.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20542741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10271375 + 10271376.

It is an arithmetic number, because the mean of its divisors is an integer number (10271376).

Almost surely, 2^20542751 is an apocalyptic number.

20542751 is a deficient number, since it is larger than the sum of its proper divisors (1).

20542751 is an equidigital number, since it uses as much as digits as its factorization.

20542751 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2800, while the sum is 26.

The square root of 20542751 is about 4532.4111684621. The cubic root of 20542751 is about 273.8753006727.

The spelling of 20542751 in words is "twenty million, five hundred forty-two thousand, seven hundred fifty-one".