19490774157 has 6 divisors (see below), whose sum is σ = 28153340462. Its totient is φ = 12993849432.

The previous prime is 19490774143. The next prime is 19490774203. The reversal of 19490774157 is 75147709491.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 19482855561 + 7918596 = 139581^2 + 2814^2 .

It is not a de Polignac number, because 19490774157 - 2⁴ = 19490774141 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 (19490774257) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1082820778 + ... + 1082820795.

Almost surely, 2^19490774157 is an apocalyptic number.

It is an amenable number.

19490774157 is a deficient number, since it is larger than the sum of its proper divisors (8662566305).

19490774157 is a wasteful number, since it uses less digits than its factorization.

19490774157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2165641579 (or 2165641576 counting only the distinct ones).

The product of its (nonzero) digits is 2222640, while the sum is 54.

The spelling of 19490774157 in words is "nineteen billion, four hundred ninety million, seven hundred seventy-four thousand, one hundred fifty-seven".