19390000081 has 8 divisors (see below), whose sum is σ = 19815593600. Its totient is φ = 18968910480.

The previous prime is 19390000067. The next prime is 19390000087. The reversal of 19390000081 is 18000009391.

19390000081 = T₁₁₃₆₉₄ + T₁₁₃₆₉₅ + T₁₁₃₆₉₆.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19390000081 is a prime.

It is a super-2 number, since 2×19390000081² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19389999998 and 19390000052.

It is not an unprimeable number, because it can be changed into a prime (19390000087) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1117275 + ... + 1134496.

It is an arithmetic number, because the mean of its divisors is an integer number (2476949200).

Almost surely, 2^19390000081 is an apocalyptic number.

19390000081 is the 113696-th centered triangular number.

It is an amenable number.

19390000081 is a deficient number, since it is larger than the sum of its proper divisors (425593519).

19390000081 is a wasteful number, since it uses less digits than its factorization.

19390000081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2251959.

The product of its (nonzero) digits is 1944, while the sum is 31.

The spelling of 19390000081 in words is "nineteen billion, three hundred ninety million, eighty-one", and thus it is an aban number.