1641797387 has 4 divisors (see below), whose sum is σ = 1698411120. Its totient is φ = 1585183656.

The previous prime is 1641797363. The next prime is 1641797393. The reversal of 1641797387 is 7837971461.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7837971461 = 787 ⋅9959303.

It is a cyclic number.

It is not a de Polignac number, because 1641797387 - 2¹⁴ = 1641781003 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1641797327) 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, 28306823 + ... + 28306880.

It is an arithmetic number, because the mean of its divisors is an integer number (424602780).

Almost surely, 2^1641797387 is an apocalyptic number.

1641797387 is a deficient number, since it is larger than the sum of its proper divisors (56613733).

1641797387 is an equidigital number, since it uses as much as digits as its factorization.

1641797387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56613732.

The product of its digits is 1778112, while the sum is 53.

The square root of 1641797387 is about 40519.0990398355. The cubic root of 1641797387 is about 1179.7043659944.

The spelling of 1641797387 in words is "one billion, six hundred forty-one million, seven hundred ninety-seven thousand, three hundred eighty-seven".