990350681 has 2 divisors, whose sum is σ = 990350682. Its totient is φ = 990350680.

The previous prime is 990350573. The next prime is 990350687. The reversal of 990350681 is 186053099.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 602260681 + 388090000 = 24541^2 + 19700^2 .

It is an emirp because it is prime and its reverse (186053099) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 990350681 - 2²² = 986156377 is a prime.

It is a super-2 number, since 2×990350681² = 1961588942714327522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (990350687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495175340 + 495175341.

It is an arithmetic number, because the mean of its divisors is an integer number (495175341).

Almost surely, 2^990350681 is an apocalyptic number.

It is an amenable number.

990350681 is a deficient number, since it is larger than the sum of its proper divisors (1).

990350681 is an equidigital number, since it uses as much as digits as its factorization.

990350681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 58320, while the sum is 41.

The square root of 990350681 is about 31469.8376386025. The cubic root of 990350681 is about 996.7731590305.

The spelling of 990350681 in words is "nine hundred ninety million, three hundred fifty thousand, six hundred eighty-one".