1640432774 has 4 divisors (see below), whose sum is σ = 2460649164. Its totient is φ = 820216386.

The previous prime is 1640432771. The next prime is 1640432779. The reversal of 1640432774 is 4772340461.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640432771) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410108192 + ... + 410108195.

It is an arithmetic number, because the mean of its divisors is an integer number (615162291).

Almost surely, 2^1640432774 is an apocalyptic number.

1640432774 is a deficient number, since it is larger than the sum of its proper divisors (820216390).

1640432774 is an equidigital number, since it uses as much as digits as its factorization.

1640432774 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 820216389.

The product of its (nonzero) digits is 112896, while the sum is 38.

The square root of 1640432774 is about 40502.2564062794. The cubic root of 1640432774 is about 1179.3774303750.

The spelling of 1640432774 in words is "one billion, six hundred forty million, four hundred thirty-two thousand, seven hundred seventy-four".