21875797 has 2 divisors, whose sum is σ = 21875798. Its totient is φ = 21875796.

The previous prime is 21875767. The next prime is 21875827. The reversal of 21875797 is 79757812.

It is a balanced prime because it is at equal distance from previous prime (21875767) and next prime (21875827).

It can be written as a sum of positive squares in only one way, i.e., 20421361 + 1454436 = 4519^2 + 1206^2 .

It is a cyclic number.

It is not a de Polignac number, because 21875797 - 2¹⁹ = 21351509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21875747) 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 as a sum of consecutive naturals, namely, 10937898 + 10937899.

It is an arithmetic number, because the mean of its divisors is an integer number (10937899).

Almost surely, 2^21875797 is an apocalyptic number.

It is an amenable number.

21875797 is a deficient number, since it is larger than the sum of its proper divisors (1).

21875797 is an equidigital number, since it uses as much as digits as its factorization.

21875797 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 246960, while the sum is 46.

The square root of 21875797 is about 4677.1569355753. The cubic root of 21875797 is about 279.6756320318.

The spelling of 21875797 in words is "twenty-one million, eight hundred seventy-five thousand, seven hundred ninety-seven".