68689440 has 72 divisors (see below), whose sum is σ = 234407628. Its totient is φ = 18316800.

The previous prime is 68689421. The next prime is 68689441. The reversal of 68689440 is 4498686.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 67963536 + 725904 = 8244^2 + 852^2 .

It is a tau number, because it is divible by the number of its divisors (72).

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 (68689441) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22411 + ... + 25290.

Almost surely, 2^68689440 is an apocalyptic number.

68689440 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

68689440 is an abundant number, since it is smaller than the sum of its proper divisors (165718188).

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

68689440 is a wasteful number, since it uses less digits than its factorization.

68689440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47722 (or 47711 counting only the distinct ones).

The product of its (nonzero) digits is 331776, while the sum is 45.

The square root of 68689440 is about 8287.9092659126. The cubic root of 68689440 is about 409.5403136704.

The spelling of 68689440 in words is "sixty-eight million, six hundred eighty-nine thousand, four hundred forty".