1861780551213 has 8 divisors (see below), whose sum is σ = 2708044438176. Its totient is φ = 1128351849200.

The previous prime is 1861780551181. The next prime is 1861780551227. The reversal of 1861780551213 is 3121550871681.

It is a happy number.

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 1861780551213 - 2⁵ = 1861780551181 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1861780551233) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28208796198 + ... + 28208796263.

It is an arithmetic number, because the mean of its divisors is an integer number (338505554772).

Almost surely, 2^{1861780551213} is an apocalyptic number.

It is an amenable number.

1861780551213 is a deficient number, since it is larger than the sum of its proper divisors (846263886963).

1861780551213 is a wasteful number, since it uses less digits than its factorization.

1861780551213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56417592475.

The product of its (nonzero) digits is 403200, while the sum is 48.

The spelling of 1861780551213 in words is "one trillion, eight hundred sixty-one billion, seven hundred eighty million, five hundred fifty-one thousand, two hundred thirteen".