1791156497 has 4 divisors (see below), whose sum is σ = 1928937780. Its totient is φ = 1653375216.

The previous prime is 1791156491. The next prime is 1791156539. The reversal of 1791156497 is 7946511971.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7946511971 = 607 ⋅13091453.

It can be written as a sum of positive squares in 2 ways, for example, as 1236506896 + 554649601 = 35164^2 + 23551^2 .

It is a cyclic number.

It is not a de Polignac number, because 1791156497 - 2¹⁰ = 1791155473 is a prime.

It is a super-2 number, since 2×1791156497² = 6416483193490622018, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1791156491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 68890622 + ... + 68890647.

It is an arithmetic number, because the mean of its divisors is an integer number (482234445).

Almost surely, 2^1791156497 is an apocalyptic number.

It is an amenable number.

1791156497 is a deficient number, since it is larger than the sum of its proper divisors (137781283).

1791156497 is a wasteful number, since it uses less digits than its factorization.

1791156497 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137781282.

The product of its digits is 476280, while the sum is 50.

The square root of 1791156497 is about 42322.0568616413. The cubic root of 1791156497 is about 1214.4449805735. Note that the first 3 decimals are identical.

The spelling of 1791156497 in words is "one billion, seven hundred ninety-one million, one hundred fifty-six thousand, four hundred ninety-seven".