1061221156164 has 288 divisors, whose sum is σ = 3196295182080. Its totient is φ = 293546778624.

The previous prime is 1061221156157. The next prime is 1061221156183. The reversal of 1061221156164 is 4616511221601.

1061221156164 is a `hidden beast` number, since 1 + 0 + 6 + 1 + 2 + 21 + 15 + 616 + 4 = 666.

It is a super-2 number, since 2×1061221156164² (a number of 25 digits) contains 22 as substring.

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

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, 144007872 + ... + 144015240.

It is an arithmetic number, because the mean of its divisors is an integer number (11098247160).

Almost surely, 2^{1061221156164} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1061221156164, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1598147591040).

1061221156164 is an abundant number, since it is smaller than the sum of its proper divisors (2135074025916).

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

1061221156164 is a wasteful number, since it uses less digits than its factorization.

1061221156164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8219 (or 8214 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 36.

Adding to 1061221156164 its reverse (4616511221601), we get a palindrome (5677732377765).

The spelling of 1061221156164 in words is "one trillion, sixty-one billion, two hundred twenty-one million, one hundred fifty-six thousand, one hundred sixty-four".