307688640 has 336 divisors, whose sum is σ = 1178625024. Its totient is φ = 67737600.

The previous prime is 307688639. The next prime is 307688657. The reversal of 307688640 is 46886703.

It is a tau number, because it is divible by the number of its divisors (336).

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 307688592 and 307688601.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1458135 + ... + 1458345.

Almost surely, 2^307688640 is an apocalyptic number.

307688640 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 307688640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (589312512).

307688640 is an abundant number, since it is smaller than the sum of its proper divisors (870936384).

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

307688640 is a wasteful number, since it uses less digits than its factorization.

307688640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 276 (or 259 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 42.

The square root of 307688640 is about 17541.0558405131. The cubic root of 307688640 is about 675.1036987458.

The spelling of 307688640 in words is "three hundred seven million, six hundred eighty-eight thousand, six hundred forty".