19490934861 has 6 divisors (see below), whose sum is σ = 28153572590. Its totient is φ = 12993956568.

The previous prime is 19490934857. The next prime is 19490934907. The reversal of 19490934861 is 16843909491.

It is a happy number.

19490934861 is a `hidden beast` number, since 1 + 9 + 490 + 93 + 4 + 8 + 61 = 666.

It can be written as a sum of positive squares in only one way, i.e., 17412122025 + 2078812836 = 131955^2 + 45594^2 .

It is not a de Polignac number, because 19490934861 - 2² = 19490934857 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19490934798 and 19490934807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19490934821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1082829706 + ... + 1082829723.

Almost surely, 2^19490934861 is an apocalyptic number.

It is an amenable number.

19490934861 is a deficient number, since it is larger than the sum of its proper divisors (8662637729).

19490934861 is a wasteful number, since it uses less digits than its factorization.

19490934861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2165659435 (or 2165659432 counting only the distinct ones).

The product of its (nonzero) digits is 1679616, while the sum is 54.

The spelling of 19490934861 in words is "nineteen billion, four hundred ninety million, nine hundred thirty-four thousand, eight hundred sixty-one".