19994122501 has 4 divisors (see below), whose sum is σ = 21170247372. Its totient is φ = 18817997632.

The previous prime is 19994122487. The next prime is 19994122531. The reversal of 19994122501 is 10522149991.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 14654313025 + 5339809476 = 121055^2 + 73074^2 .

It is a cyclic number.

It is not a de Polignac number, because 19994122501 - 2⁵ = 19994122469 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19994122531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 588062410 + ... + 588062443.

It is an arithmetic number, because the mean of its divisors is an integer number (5292561843).

Almost surely, 2^19994122501 is an apocalyptic number.

It is an amenable number.

19994122501 is a deficient number, since it is larger than the sum of its proper divisors (1176124871).

19994122501 is a wasteful number, since it uses less digits than its factorization.

19994122501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1176124870.

The product of its (nonzero) digits is 58320, while the sum is 43.

The spelling of 19994122501 in words is "nineteen billion, nine hundred ninety-four million, one hundred twenty-two thousand, five hundred one".