21875747 has 2 divisors, whose sum is σ = 21875748. Its totient is φ = 21875746.

The previous prime is 21875713. The next prime is 21875767. The reversal of 21875747 is 74757812.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21875747 - 2¹⁴ = 21859363 is a prime.

It is not a weakly prime, because it can be changed into another prime (21875767) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10937873 + 10937874.

It is an arithmetic number, because the mean of its divisors is an integer number (10937874).

Almost surely, 2^21875747 is an apocalyptic number.

21875747 is a deficient number, since it is larger than the sum of its proper divisors (1).

21875747 is an equidigital number, since it uses as much as digits as its factorization.

21875747 is an evil number, because the sum of its binary digits is even.

The product of its digits is 109760, while the sum is 41.

The square root of 21875747 is about 4677.1515904448. The cubic root of 21875747 is about 279.6754189532.

It can be divided in two parts, 21875 and 747, that added together give a palindrome (22622).

The spelling of 21875747 in words is "twenty-one million, eight hundred seventy-five thousand, seven hundred forty-seven".