19421372917501 has 2 divisors, whose sum is σ = 19421372917502. Its totient is φ = 19421372917500.

The previous prime is 19421372917483. The next prime is 19421372917543. The reversal of 19421372917501 is 10571927312491.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18709526353401 + 711846564100 = 4325451^2 + 843710^2 .

It is an emirp because it is prime and its reverse (10571927312491) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19421372917501 - 2⁴¹ = 17222349661949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19421372917591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9710686458750 + 9710686458751.

It is an arithmetic number, because the mean of its divisors is an integer number (9710686458751).

Almost surely, 2^{19421372917501} is an apocalyptic number.

It is an amenable number.

19421372917501 is a deficient number, since it is larger than the sum of its proper divisors (1).

19421372917501 is an equidigital number, since it uses as much as digits as its factorization.

19421372917501 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 952560, while the sum is 52.

The spelling of 19421372917501 in words is "nineteen trillion, four hundred twenty-one billion, three hundred seventy-two million, nine hundred seventeen thousand, five hundred one".