1993908240 has 120 divisors (see below), whose sum is σ = 7090146648. Its totient is φ = 500428800.

The previous prime is 1993908239. The next prime is 1993908247. The reversal of 1993908240 is 428093991.

1993908240 is a `hidden beast` number, since 19 + 9 + 390 + 8 + 240 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 222845184 + 1771063056 = 14928^2 + 42084^2 .

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (1993908247) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 69211 + ... + 93690.

Almost surely, 2^1993908240 is an apocalyptic number.

1993908240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1993908240 is an abundant number, since it is smaller than the sum of its proper divisors (5096238408).

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

1993908240 is a wasteful number, since it uses less digits than its factorization.

1993908240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162937 (or 162928 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 45.

The square root of 1993908240 is about 44653.1996613904. The cubic root of 1993908240 is about 1258.6405594977.

The spelling of 1993908240 in words is "one billion, nine hundred ninety-three million, nine hundred eight thousand, two hundred forty".