1891434497 has 8 divisors (see below), whose sum is σ = 1917142920. Its totient is φ = 1865825280.

The previous prime is 1891434481. The next prime is 1891434499. The reversal of 1891434497 is 7944341981.

It can be written as a sum of positive squares in 4 ways, for example, as 141376 + 1891293121 = 376^2 + 43489^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1891434497 - 2⁴ = 1891434481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1891434499) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13997 + ... + 63077.

It is an arithmetic number, because the mean of its divisors is an integer number (239642865).

It is a Proth number, since it is equal to 28861 ⋅ 2¹⁶ + 1 and 28861 < 2¹⁶.

Almost surely, 2^1891434497 is an apocalyptic number.

It is an amenable number.

1891434497 is a deficient number, since it is larger than the sum of its proper divisors (25708423).

1891434497 is an equidigital number, since it uses as much as digits as its factorization.

1891434497 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49603.

The product of its digits is 870912, while the sum is 50.

The square root of 1891434497 is about 43490.6253921463. The cubic root of 1891434497 is about 1236.6983135571.

The spelling of 1891434497 in words is "one billion, eight hundred ninety-one million, four hundred thirty-four thousand, four hundred ninety-seven".