19393940 has 24 divisors (see below), whose sum is σ = 43123752. Its totient is φ = 7301120.

The previous prime is 19393937. The next prime is 19393951. The reversal of 19393940 is 4939391.

It can be written as a sum of positive squares in 4 ways, for example, as 3104644 + 16289296 = 1762^2 + 4036^2 .

It is a super-2 number, since 2×19393940² = 752249817447200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 19393894 and 19393903.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28181 + ... + 28860.

It is an arithmetic number, because the mean of its divisors is an integer number (1796823).

Almost surely, 2^19393940 is an apocalyptic number.

19393940 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19393940 is an abundant number, since it is smaller than the sum of its proper divisors (23729812).

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

19393940 is a wasteful number, since it uses less digits than its factorization.

19393940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57067 (or 57065 counting only the distinct ones).

The product of its (nonzero) digits is 26244, while the sum is 38.

The square root of 19393940 is about 4403.8551293157. The cubic root of 19393940 is about 268.6717572843.

The spelling of 19393940 in words is "nineteen million, three hundred ninety-three thousand, nine hundred forty".