9901621519 has 2 divisors, whose sum is σ = 9901621520. Its totient is φ = 9901621518.

The previous prime is 9901621517. The next prime is 9901621591. The reversal of 9901621519 is 9151261099.

Together with next prime (9901621591) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 9901621519 - 2¹ = 9901621517 is a prime.

It is a super-2 number, since 2×9901621519² (a number of 21 digits) contains 22 as substring.

Together with 9901621517, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9901621517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4950810759 + 4950810760.

It is an arithmetic number, because the mean of its divisors is an integer number (4950810760).

Almost surely, 2^9901621519 is an apocalyptic number.

9901621519 is a deficient number, since it is larger than the sum of its proper divisors (1).

9901621519 is an equidigital number, since it uses as much as digits as its factorization.

9901621519 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 43740, while the sum is 43.

The square root of 9901621519 is about 99506.8918165973. The cubic root of 9901621519 is about 2147.3463940297.

The spelling of 9901621519 in words is "nine billion, nine hundred one million, six hundred twenty-one thousand, five hundred nineteen".