1641540497 has 2 divisors, whose sum is σ = 1641540498. Its totient is φ = 1641540496.

The previous prime is 1641540457. The next prime is 1641540541. The reversal of 1641540497 is 7940451461.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 919059856 + 722480641 = 30316^2 + 26879^2 .

It is an emirp because it is prime and its reverse (7940451461) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1641540497 - 2²⁰ = 1640491921 is a prime.

It is not a weakly prime, because it can be changed into another prime (1641540457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 820770248 + 820770249.

It is an arithmetic number, because the mean of its divisors is an integer number (820770249).

Almost surely, 2^1641540497 is an apocalyptic number.

It is an amenable number.

1641540497 is a deficient number, since it is larger than the sum of its proper divisors (1).

1641540497 is an equidigital number, since it uses as much as digits as its factorization.

1641540497 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 120960, while the sum is 41.

The square root of 1641540497 is about 40515.9289292495. The cubic root of 1641540497 is about 1179.6428338255.

The spelling of 1641540497 in words is "one billion, six hundred forty-one million, five hundred forty thousand, four hundred ninety-seven".