64021387 has 2 divisors, whose sum is σ = 64021388. Its totient is φ = 64021386.

The previous prime is 64021369. The next prime is 64021421. The reversal of 64021387 is 78312046.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64021387 is a prime.

It is not a weakly prime, because it can be changed into another prime (64021327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32010693 + 32010694.

It is an arithmetic number, because the mean of its divisors is an integer number (32010694).

Almost surely, 2^64021387 is an apocalyptic number.

64021387 is a deficient number, since it is larger than the sum of its proper divisors (1).

64021387 is an equidigital number, since it uses as much as digits as its factorization.

64021387 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 64021387 is about 8001.3365758478. The cubic root of 64021387 is about 400.0445512878.

The spelling of 64021387 in words is "sixty-four million, twenty-one thousand, three hundred eighty-seven".