997638011 has 2 divisors, whose sum is σ = 997638012. Its totient is φ = 997638010.

The previous prime is 997638007. The next prime is 997638029. The reversal of 997638011 is 110836799.

It is a weak prime.

It is an emirp because it is prime and its reverse (110836799) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 997638011 - 2² = 997638007 is a prime.

It is a super-2 number, since 2×997638011² = 1990563201984072242, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (997638071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 498819005 + 498819006.

It is an arithmetic number, because the mean of its divisors is an integer number (498819006).

Almost surely, 2^997638011 is an apocalyptic number.

997638011 is a deficient number, since it is larger than the sum of its proper divisors (1).

997638011 is an equidigital number, since it uses as much as digits as its factorization.

997638011 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 81648, while the sum is 44.

The square root of 997638011 is about 31585.4081974573. The cubic root of 997638011 is about 999.2120496306.

The spelling of 997638011 in words is "nine hundred ninety-seven million, six hundred thirty-eight thousand, eleven".