6402309840 has 60 divisors (see below), whose sum is σ = 21501092964. Its totient is φ = 1707282432.

The previous prime is 6402309833. The next prime is 6402309869. The reversal of 6402309840 is 489032046.

It is a happy number.

6402309840 is a `hidden beast` number, since 640 + 2 + 3 + 0 + 9 + 8 + 4 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 2868245136 + 3534064704 = 53556^2 + 59448^2 .

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 6402309795 and 6402309804.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4445329 + ... + 4446768.

Almost surely, 2^6402309840 is an apocalyptic number.

6402309840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

6402309840 is an abundant number, since it is smaller than the sum of its proper divisors (15098783124).

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

6402309840 is a wasteful number, since it uses less digits than its factorization.

6402309840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8892116 (or 8892107 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 36.

The square root of 6402309840 is about 80014.4351976567. The cubic root of 6402309840 is about 1856.8588675699.

The spelling of 6402309840 in words is "six billion, four hundred two million, three hundred nine thousand, eight hundred forty".