650661001 has 4 divisors (see below), whose sum is σ = 650734612. Its totient is φ = 650587392.

The previous prime is 650660999. The next prime is 650661029. The reversal of 650661001 is 100166056.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 158886025 + 491774976 = 12605^2 + 22176^2 .

It is a cyclic number.

It is not a de Polignac number, because 650661001 - 2¹ = 650660999 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (650661041) 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, 21396 + ... + 41941.

It is an arithmetic number, because the mean of its divisors is an integer number (162683653).

Almost surely, 2^650661001 is an apocalyptic number.

It is an amenable number.

650661001 is a deficient number, since it is larger than the sum of its proper divisors (73611).

650661001 is a wasteful number, since it uses less digits than its factorization.

650661001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73610.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 650661001 is about 25508.0575701091. The cubic root of 650661001 is about 866.5326391525.

The spelling of 650661001 in words is "six hundred fifty million, six hundred sixty-one thousand, one".