1820497517 has 2 divisors, whose sum is σ = 1820497518. Its totient is φ = 1820497516.

The previous prime is 1820497501. The next prime is 1820497543. The reversal of 1820497517 is 7157940281.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1063477321 + 757020196 = 32611^2 + 27514^2 .

It is a cyclic number.

It is not a de Polignac number, because 1820497517 - 2⁴ = 1820497501 is a prime.

It is a super-2 number, since 2×1820497517² = 6628422418806330578, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1820497117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 910248758 + 910248759.

It is an arithmetic number, because the mean of its divisors is an integer number (910248759).

Almost surely, 2^1820497517 is an apocalyptic number.

It is an amenable number.

1820497517 is a deficient number, since it is larger than the sum of its proper divisors (1).

1820497517 is an equidigital number, since it uses as much as digits as its factorization.

1820497517 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 141120, while the sum is 44.

The square root of 1820497517 is about 42667.2886061442. The cubic root of 1820497517 is about 1221.0403910777.

The spelling of 1820497517 in words is "one billion, eight hundred twenty million, four hundred ninety-seven thousand, five hundred seventeen".