61439400128 has 28 divisors (see below), whose sum is σ = 121936044672. Its totient is φ = 30715357440.

The previous prime is 61439400097. The next prime is 61439400131. The reversal of 61439400128 is 82100493416.

It is a junction number, because it is equal to n+sod(n) for n = 61439400091 and 61439400100.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 415058 + ... + 543278.

Almost surely, 2^61439400128 is an apocalyptic number.

It is an amenable number.

61439400128 is a deficient number, since it is larger than the sum of its proper divisors (60496644544).

61439400128 is a wasteful number, since it uses less digits than its factorization.

61439400128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135720 (or 135710 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 38.

The spelling of 61439400128 in words is "sixty-one billion, four hundred thirty-nine million, four hundred thousand, one hundred twenty-eight".