61531231556 has 12 divisors (see below), whose sum is σ = 107709013440. Its totient is φ = 30757227720.

The previous prime is 61531231513. The next prime is 61531231577. The reversal of 61531231556 is 65513213516.

It is a super-2 number, since 2×61531231556² (a number of 22 digits) contains 22 as substring.

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, 2080496 + ... + 2109863.

It is an arithmetic number, because the mean of its divisors is an integer number (8975751120).

Almost surely, 2^61531231556 is an apocalyptic number.

It is an amenable number.

61531231556 is a deficient number, since it is larger than the sum of its proper divisors (46177781884).

61531231556 is a wasteful number, since it uses less digits than its factorization.

61531231556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4194034 (or 4194032 counting only the distinct ones).

The product of its digits is 81000, while the sum is 38.

The spelling of 61531231556 in words is "sixty-one billion, five hundred thirty-one million, two hundred thirty-one thousand, five hundred fifty-six".