139947905 has 8 divisors (see below), whose sum is σ = 171510912. Its totient is φ = 109576048.

The previous prime is 139947889. The next prime is 139947911. The reversal of 139947905 is 509749931.

139947905 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 139947905 - 2⁴ = 139947889 is a prime.

It is a super-2 number, since 2×139947905² = 39170832227778050, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (47).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 139947905.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 297527 + ... + 297996.

It is an arithmetic number, because the mean of its divisors is an integer number (21438864).

Almost surely, 2^139947905 is an apocalyptic number.

It is an amenable number.

139947905 is a deficient number, since it is larger than the sum of its proper divisors (31563007).

139947905 is an equidigital number, since it uses as much as digits as its factorization.

139947905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 595575.

The product of its (nonzero) digits is 306180, while the sum is 47.

The square root of 139947905 is about 11829.9579458255. The cubic root of 139947905 is about 519.1849967234.

The spelling of 139947905 in words is "one hundred thirty-nine million, nine hundred forty-seven thousand, nine hundred five".