1661120322771 has 256 divisors, whose sum is σ = 3151199600640. Its totient is φ = 752438108160.

The previous prime is 1661120322751. The next prime is 1661120322781. The reversal of 1661120322771 is 1772230211661.

It is not a de Polignac number, because 1661120322771 - 2⁵ = 1661120322739 is a prime.

It is a super-2 number, since 2×1661120322771² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (1661120322751) by changing a digit.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 620514285 + ... + 620516961.

It is an arithmetic number, because the mean of its divisors is an integer number (12309373440).

Almost surely, 2^{1661120322771} is an apocalyptic number.

1661120322771 is a deficient number, since it is larger than the sum of its proper divisors (1490079277869).

1661120322771 is a wasteful number, since it uses less digits than its factorization.

1661120322771 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2994.

The product of its (nonzero) digits is 42336, while the sum is 39.

It can be divided in two parts, 1661120 and 322771, that added together give a palindrome (1983891).

The spelling of 1661120322771 in words is "one trillion, six hundred sixty-one billion, one hundred twenty million, three hundred twenty-two thousand, seven hundred seventy-one".