139481778 has 8 divisors (see below), whose sum is σ = 278963568. Its totient is φ = 46493924.

The previous prime is 139481777. The next prime is 139481789. The reversal of 139481778 is 877184931.

It is a sphenic number, since it is the product of 3 distinct primes.

139481778 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (139481773) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11623476 + ... + 11623487.

It is an arithmetic number, because the mean of its divisors is an integer number (34870446).

Almost surely, 2^139481778 is an apocalyptic number.

139481778 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

139481778 is a wasteful number, since it uses less digits than its factorization.

139481778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23246968.

The product of its digits is 338688, while the sum is 48.

The square root of 139481778 is about 11810.2403870539. The cubic root of 139481778 is about 518.6079359760.

The spelling of 139481778 in words is "one hundred thirty-nine million, four hundred eighty-one thousand, seven hundred seventy-eight".