2491821097 has 2 divisors, whose sum is σ = 2491821098. Its totient is φ = 2491821096.

The previous prime is 2491821077. The next prime is 2491821107. The reversal of 2491821097 is 7901281942.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2151197161 + 340623936 = 46381^2 + 18456^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2491821097 is a prime.

It is not a weakly prime, because it can be changed into another prime (2491821077) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1245910548 + 1245910549.

It is an arithmetic number, because the mean of its divisors is an integer number (1245910549).

Almost surely, 2^2491821097 is an apocalyptic number.

It is an amenable number.

2491821097 is a deficient number, since it is larger than the sum of its proper divisors (1).

2491821097 is an equidigital number, since it uses as much as digits as its factorization.

2491821097 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72576, while the sum is 43.

The square root of 2491821097 is about 49918.1439658968. The cubic root of 2491821097 is about 1355.7271274251.

The spelling of 2491821097 in words is "two billion, four hundred ninety-one million, eight hundred twenty-one thousand, ninety-seven".