650216777821 has 4 divisors (see below), whose sum is σ = 700233453052. Its totient is φ = 600200102592.

The previous prime is 650216777813. The next prime is 650216777831. The reversal of 650216777821 is 128777612056.

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 449637302500 + 200579475321 = 670550^2 + 447861^2 .

It is a cyclic number.

It is not a de Polignac number, because 650216777821 - 2³ = 650216777813 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (650216777831) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25008337596 + ... + 25008337621.

It is an arithmetic number, because the mean of its divisors is an integer number (175058363263).

Almost surely, 2^650216777821 is an apocalyptic number.

It is an amenable number.

650216777821 is a deficient number, since it is larger than the sum of its proper divisors (50016675231).

650216777821 is a wasteful number, since it uses less digits than its factorization.

650216777821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50016675230.

The product of its (nonzero) digits is 1975680, while the sum is 52.

The spelling of 650216777821 in words is "six hundred fifty billion, two hundred sixteen million, seven hundred seventy-seven thousand, eight hundred twenty-one".