138910778820 has 384 divisors, whose sum is σ = 483375513600. Its totient is φ = 32833382400.

The previous prime is 138910778779. The next prime is 138910778861. The reversal of 138910778820 is 28877019831.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (138910778779) and next prime (138910778861).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 44506860 + ... + 44509980.

It is an arithmetic number, because the mean of its divisors is an integer number (1258790400).

Almost surely, 2^138910778820 is an apocalyptic number.

138910778820 is a gapful number since it is divisible by the number (10) 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 138910778820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (241687756800).

138910778820 is an abundant number, since it is smaller than the sum of its proper divisors (344464734780).

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

138910778820 is a wasteful number, since it uses less digits than its factorization.

138910778820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3336 (or 3328 counting only the distinct ones).

The product of its (nonzero) digits is 1354752, while the sum is 54.

The spelling of 138910778820 in words is "one hundred thirty-eight billion, nine hundred ten million, seven hundred seventy-eight thousand, eight hundred twenty".