1011157216721 has 4 divisors (see below), whose sum is σ = 1011165093744. Its totient is φ = 1011149339700.

The previous prime is 1011157216679. The next prime is 1011157216733. The reversal of 1011157216721 is 1276127511101.

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 a cyclic number.

It is not a de Polignac number, because 1011157216721 - 2²² = 1011153022417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1011157216621) 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, 3742715 + ... + 4003776.

It is an arithmetic number, because the mean of its divisors is an integer number (252791273436).

Almost surely, 2^{1011157216721} is an apocalyptic number.

It is an amenable number.

1011157216721 is a deficient number, since it is larger than the sum of its proper divisors (7877023).

1011157216721 is an equidigital number, since it uses as much as digits as its factorization.

1011157216721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7877022.

The product of its (nonzero) digits is 5880, while the sum is 35.

The spelling of 1011157216721 in words is "one trillion, eleven billion, one hundred fifty-seven million, two hundred sixteen thousand, seven hundred twenty-one".