68990040 has 144 divisors (see below), whose sum is σ = 260891280. Its totient is φ = 15765120.

The previous prime is 68990027. The next prime is 68990059. The reversal of 68990040 is 4009986.

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 = 68989977 and 68990004.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 15685 + ... + 19595.

It is an arithmetic number, because the mean of its divisors is an integer number (1811745).

Almost surely, 2^68990040 is an apocalyptic number.

68990040 is a gapful number since it is divisible by the number (60) 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 68990040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (130445640).

68990040 is an abundant number, since it is smaller than the sum of its proper divisors (191901240).

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

68990040 is a wasteful number, since it uses less digits than its factorization.

68990040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3942 (or 3928 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 68990040 is about 8306.0243197332. The cubic root of 68990040 is about 410.1368569497.

The spelling of 68990040 in words is "sixty-eight million, nine hundred ninety thousand, forty".