64783021 has 2 divisors, whose sum is σ = 64783022. Its totient is φ = 64783020.

The previous prime is 64783009. The next prime is 64783049. The reversal of 64783021 is 12038746.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 43494025 + 21288996 = 6595^2 + 4614^2 .

It is a cyclic number.

It is not a de Polignac number, because 64783021 - 2¹¹ = 64780973 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64783051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32391510 + 32391511.

It is an arithmetic number, because the mean of its divisors is an integer number (32391511).

Almost surely, 2^64783021 is an apocalyptic number.

It is an amenable number.

64783021 is a deficient number, since it is larger than the sum of its proper divisors (1).

64783021 is an equidigital number, since it uses as much as digits as its factorization.

64783021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 64783021 is about 8048.7900332907. The cubic root of 64783021 is about 401.6246858057.

The spelling of 64783021 in words is "sixty-four million, seven hundred eighty-three thousand, twenty-one".