1161721611572 has 24 divisors (see below), whose sum is σ = 2046871524936. Its totient is φ = 576914577408.

The previous prime is 1161721611553. The next prime is 1161721611581. The reversal of 1161721611572 is 2751161271611.

It can be written as a sum of positive squares in 4 ways, for example, as 225231871396 + 936489740176 = 474586^2 + 967724^2 .

It is a super-2 number, since 2×1161721611572² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1328093 + ... + 2021700.

It is an arithmetic number, because the mean of its divisors is an integer number (85286313539).

Almost surely, 2^{1161721611572} is an apocalyptic number.

It is an amenable number.

1161721611572 is a deficient number, since it is larger than the sum of its proper divisors (885149913364).

1161721611572 is a wasteful number, since it uses less digits than its factorization.

1161721611572 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3350387 (or 3350385 counting only the distinct ones).

The product of its digits is 35280, while the sum is 41.

The spelling of 1161721611572 in words is "one trillion, one hundred sixty-one billion, seven hundred twenty-one million, six hundred eleven thousand, five hundred seventy-two".