21712753 has 2 divisors, whose sum is σ = 21712754. Its totient is φ = 21712752.

The previous prime is 21712729. The next prime is 21712781. The reversal of 21712753 is 35721712.

It is an a-pointer prime, because the next prime (21712781) can be obtained adding 21712753 to its sum of digits (28).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18515809 + 3196944 = 4303^2 + 1788^2 .

It is a cyclic number.

It is not a de Polignac number, because 21712753 - 2⁹ = 21712241 is a prime.

It is not a weakly prime, because it can be changed into another prime (21712783) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10856376 + 10856377.

It is an arithmetic number, because the mean of its divisors is an integer number (10856377).

Almost surely, 2^21712753 is an apocalyptic number.

It is an amenable number.

21712753 is a deficient number, since it is larger than the sum of its proper divisors (1).

21712753 is an equidigital number, since it uses as much as digits as its factorization.

21712753 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2940, while the sum is 28.

The square root of 21712753 is about 4659.6945178842. The cubic root of 21712753 is about 278.9790754381.

The spelling of 21712753 in words is "twenty-one million, seven hundred twelve thousand, seven hundred fifty-three".