65211649 has 4 divisors (see below), whose sum is σ = 66974164. Its totient is φ = 63449136.

The previous prime is 65211613. The next prime is 65211661. The reversal of 65211649 is 94611256.

65211649 = 902² + 903² + ... + 975².

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 56550400 + 8661249 = 7520^2 + 2943^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65211649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65211149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 881202 + ... + 881275.

It is an arithmetic number, because the mean of its divisors is an integer number (16743541).

Almost surely, 2^65211649 is an apocalyptic number.

It is an amenable number.

65211649 is a deficient number, since it is larger than the sum of its proper divisors (1762515).

65211649 is a wasteful number, since it uses less digits than its factorization.

65211649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1762514.

The product of its digits is 12960, while the sum is 34.

The square root of 65211649 is about 8075.3729944814. The cubic root of 65211649 is about 402.5085043790.

The spelling of 65211649 in words is "sixty-five million, two hundred eleven thousand, six hundred forty-nine".