68138992 has 40 divisors (see below), whose sum is σ = 144312192. Its totient is φ = 31027200.

The previous prime is 68138977. The next prime is 68138999. The reversal of 68138992 is 29983186.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68138999) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4392 + ... + 12472.

Almost surely, 2^68138992 is an apocalyptic number.

68138992 is a gapful number since it is divisible by the number (62) 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 68138992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72156096).

68138992 is an abundant number, since it is smaller than the sum of its proper divisors (76173200).

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

68138992 is a wasteful number, since it uses less digits than its factorization.

68138992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8137 (or 8131 counting only the distinct ones).

The product of its digits is 186624, while the sum is 46.

The square root of 68138992 is about 8254.6345770119. The cubic root of 68138992 is about 408.4434176976.

The spelling of 68138992 in words is "sixty-eight million, one hundred thirty-eight thousand, nine hundred ninety-two".