1661112622620 has 288 divisors, whose sum is σ = 5738867656704. Its totient is φ = 384977049600.

The previous prime is 1661112622577. The next prime is 1661112622649. The reversal of 1661112622620 is 262262111661.

1661112622620 is a `hidden beast` number, since 1 + 6 + 6 + 1 + 1 + 1 + 2 + 6 + 22 + 620 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 93940180 + ... + 93957860.

It is an arithmetic number, because the mean of its divisors is an integer number (19926623808).

Almost surely, 2^{1661112622620} is an apocalyptic number.

1661112622620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1661112622620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2869433828352).

1661112622620 is an abundant number, since it is smaller than the sum of its proper divisors (4077755034084).

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

1661112622620 is a wasteful number, since it uses less digits than its factorization.

1661112622620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19793 (or 19788 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The spelling of 1661112622620 in words is "one trillion, six hundred sixty-one billion, one hundred twelve million, six hundred twenty-two thousand, six hundred twenty".