1091621166357 has 4 divisors (see below), whose sum is σ = 1455494888480. Its totient is φ = 727747444236.

The previous prime is 1091621166289. The next prime is 1091621166373. The reversal of 1091621166357 is 7536611261901.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1091621166357 - 2²² = 1091616972053 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1091621166557) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 181936861057 + ... + 181936861062.

It is an arithmetic number, because the mean of its divisors is an integer number (363873722120).

Almost surely, 2^{1091621166357} is an apocalyptic number.

It is an amenable number.

1091621166357 is a deficient number, since it is larger than the sum of its proper divisors (363873722123).

1091621166357 is an equidigital number, since it uses as much as digits as its factorization.

1091621166357 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 363873722122.

The product of its (nonzero) digits is 408240, while the sum is 48.

The spelling of 1091621166357 in words is "one trillion, ninety-one billion, six hundred twenty-one million, one hundred sixty-six thousand, three hundred fifty-seven".