2001521276609 has 2 divisors, whose sum is σ = 2001521276610. Its totient is φ = 2001521276608.

The previous prime is 2001521276527. The next prime is 2001521276683. The reversal of 2001521276609 is 9066721251002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1637447818384 + 364073458225 = 1279628^2 + 603385^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2001521276609 is a prime.

It is not a weakly prime, because it can be changed into another prime (2001521206609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000760638304 + 1000760638305.

It is an arithmetic number, because the mean of its divisors is an integer number (1000760638305).

Almost surely, 2^{2001521276609} is an apocalyptic number.

It is an amenable number.

2001521276609 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001521276609 is an equidigital number, since it uses as much as digits as its factorization.

2001521276609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 90720, while the sum is 41.

The spelling of 2001521276609 in words is "two trillion, one billion, five hundred twenty-one million, two hundred seventy-six thousand, six hundred nine".