19403940392 has 8 divisors (see below), whose sum is σ = 36382388250. Its totient is φ = 9701970192.

The previous prime is 19403940371. The next prime is 19403940407. The reversal of 19403940392 is 29304930491.

It can be written as a sum of positive squares in only one way, i.e., 19150684996 + 253255396 = 138386^2 + 15914^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×19403940392² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1212746267 + ... + 1212746282.

Almost surely, 2^19403940392 is an apocalyptic number.

It is an amenable number.

19403940392 is a deficient number, since it is larger than the sum of its proper divisors (16978447858).

19403940392 is a wasteful number, since it uses less digits than its factorization.

19403940392 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2425492555 (or 2425492551 counting only the distinct ones).

The product of its (nonzero) digits is 209952, while the sum is 44.

Subtracting 19403940392 from its reverse (29304930491), we obtain a palindrome (9900990099).

The spelling of 19403940392 in words is "nineteen billion, four hundred three million, nine hundred forty thousand, three hundred ninety-two".