1861211535656 has 64 divisors (see below), whose sum is σ = 3820446043200. Its totient is φ = 843025075200.

The previous prime is 1861211535647. The next prime is 1861211535661. The reversal of 1861211535656 is 6565351121681.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 61998506 + ... + 62028518.

It is an arithmetic number, because the mean of its divisors is an integer number (59694469425).

Almost surely, 2^{1861211535656} is an apocalyptic number.

It is an amenable number.

1861211535656 is an abundant number, since it is smaller than the sum of its proper divisors (1959234507544).

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

1861211535656 is a wasteful number, since it uses less digits than its factorization.

1861211535656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32490 (or 32486 counting only the distinct ones).

The product of its digits is 1296000, while the sum is 50.

The spelling of 1861211535656 in words is "one trillion, eight hundred sixty-one billion, two hundred eleven million, five hundred thirty-five thousand, six hundred fifty-six".