649963421 has 2 divisors, whose sum is σ = 649963422. Its totient is φ = 649963420.

The previous prime is 649963387. The next prime is 649963459. The reversal of 649963421 is 124369946.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 647448025 + 2515396 = 25445^2 + 1586^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-649963421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (649963471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 324981710 + 324981711.

It is an arithmetic number, because the mean of its divisors is an integer number (324981711).

Almost surely, 2^649963421 is an apocalyptic number.

It is an amenable number.

649963421 is a deficient number, since it is larger than the sum of its proper divisors (1).

649963421 is an equidigital number, since it uses as much as digits as its factorization.

649963421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 279936, while the sum is 44.

The square root of 649963421 is about 25494.3801846603. The cubic root of 649963421 is about 866.2228557231. Note that the first 3 decimals are identical.

The spelling of 649963421 in words is "six hundred forty-nine million, nine hundred sixty-three thousand, four hundred twenty-one".