1991454529 has 4 divisors (see below), whose sum is σ = 2005781680. Its totient is φ = 1977127380.

The previous prime is 1991454499. The next prime is 1991454593. The reversal of 1991454529 is 9254541991.

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, and also an emirpimes, since its reverse is a distinct semiprime: 9254541991 = 17 ⋅544384823.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1991454529 is a prime.

It is a super-2 number, since 2×1991454529² = 7931782282149223682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1991454599) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7163367 + ... + 7163644.

It is an arithmetic number, because the mean of its divisors is an integer number (501445420).

Almost surely, 2^1991454529 is an apocalyptic number.

It is an amenable number.

1991454529 is a deficient number, since it is larger than the sum of its proper divisors (14327151).

1991454529 is a wasteful number, since it uses less digits than its factorization.

1991454529 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14327150.

The product of its digits is 583200, while the sum is 49.

The square root of 1991454529 is about 44625.7160054603. The cubic root of 1991454529 is about 1258.1240516278.

The spelling of 1991454529 in words is "one billion, nine hundred ninety-one million, four hundred fifty-four thousand, five hundred twenty-nine".