19749273390 has 448 divisors, whose sum is σ = 67177423872. Its totient is φ = 4059072000.

The previous prime is 19749273359. The next prime is 19749273433. The reversal of 19749273390 is 9337294791.

19749273390 is a `hidden beast` number, since 197 + 49 + 27 + 3 + 390 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 223 ways as a sum of consecutive naturals, for example, 84760714 + ... + 84760946.

Almost surely, 2^19749273390 is an apocalyptic number.

19749273390 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 19749273390, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33588711936).

19749273390 is an abundant number, since it is smaller than the sum of its proper divisors (47428150482).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19749273390 is a wasteful number, since it uses less digits than its factorization.

19749273390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 427 (or 412 counting only the distinct ones).

The product of its (nonzero) digits is 2571912, while the sum is 54.

The spelling of 19749273390 in words is "nineteen billion, seven hundred forty-nine million, two hundred seventy-three thousand, three hundred ninety".