21625673 has 2 divisors, whose sum is σ = 21625674. Its totient is φ = 21625672.

The previous prime is 21625661. The next prime is 21625679. The reversal of 21625673 is 37652612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21501769 + 123904 = 4637^2 + 352^2 .

It is a cyclic number.

It is not a de Polignac number, because 21625673 - 2¹² = 21621577 is a prime.

It is not a weakly prime, because it can be changed into another prime (21625679) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10812836 + 10812837.

It is an arithmetic number, because the mean of its divisors is an integer number (10812837).

Almost surely, 2^21625673 is an apocalyptic number.

It is an amenable number.

21625673 is a deficient number, since it is larger than the sum of its proper divisors (1).

21625673 is an equidigital number, since it uses as much as digits as its factorization.

21625673 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15120, while the sum is 32.

The square root of 21625673 is about 4650.3411702799. The cubic root of 21625673 is about 278.6056229150.

The spelling of 21625673 in words is "twenty-one million, six hundred twenty-five thousand, six hundred seventy-three".