2009021981651 has 2 divisors, whose sum is σ = 2009021981652. Its totient is φ = 2009021981650.

The previous prime is 2009021981623. The next prime is 2009021981657. The reversal of 2009021981651 is 1561891209002.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2009021981651 - 2²² = 2009017787347 is a prime.

It is not a weakly prime, because it can be changed into another prime (2009021981657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1004510990825 + 1004510990826.

It is an arithmetic number, because the mean of its divisors is an integer number (1004510990826).

Almost surely, 2^{2009021981651} is an apocalyptic number.

2009021981651 is a deficient number, since it is larger than the sum of its proper divisors (1).

2009021981651 is an equidigital number, since it uses as much as digits as its factorization.

2009021981651 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 77760, while the sum is 44.

The spelling of 2009021981651 in words is "two trillion, nine billion, twenty-one million, nine hundred eighty-one thousand, six hundred fifty-one".