19642600381 has 2 divisors, whose sum is σ = 19642600382. Its totient is φ = 19642600380.

The previous prime is 19642600321. The next prime is 19642600391. The reversal of 19642600381 is 18300624691.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18265522500 + 1377077881 = 135150^2 + 37109^2 .

It is an emirp because it is prime and its reverse (18300624691) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19642600381 - 2⁹ = 19642599869 is a prime.

It is a super-2 number, since 2×19642600381² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19642600321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9821300190 + 9821300191.

It is an arithmetic number, because the mean of its divisors is an integer number (9821300191).

Almost surely, 2^19642600381 is an apocalyptic number.

It is an amenable number.

19642600381 is a deficient number, since it is larger than the sum of its proper divisors (1).

19642600381 is an equidigital number, since it uses as much as digits as its factorization.

19642600381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 62208, while the sum is 40.

The spelling of 19642600381 in words is "nineteen billion, six hundred forty-two million, six hundred thousand, three hundred eighty-one".