1491955645 has 4 divisors (see below), whose sum is σ = 1790346780. Its totient is φ = 1193564512.

The previous prime is 1491955637. The next prime is 1491955657. The reversal of 1491955645 is 5465591941.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 678394116 + 813561529 = 26046^2 + 28523^2 .

It is a cyclic number.

It is not a de Polignac number, because 1491955645 - 2³ = 1491955637 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 149195560 + ... + 149195569.

It is an arithmetic number, because the mean of its divisors is an integer number (447586695).

Almost surely, 2^1491955645 is an apocalyptic number.

It is an amenable number.

1491955645 is a deficient number, since it is larger than the sum of its proper divisors (298391135).

1491955645 is an equidigital number, since it uses as much as digits as its factorization.

1491955645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 298391134.

The product of its digits is 972000, while the sum is 49.

The square root of 1491955645 is about 38625.8416736775. The cubic root of 1491955645 is about 1142.6642429152.

The spelling of 1491955645 in words is "one billion, four hundred ninety-one million, nine hundred fifty-five thousand, six hundred forty-five".