6440845154 has 4 divisors (see below), whose sum is σ = 9661267734. Its totient is φ = 3220422576.

The previous prime is 6440845141. The next prime is 6440845157. The reversal of 6440845154 is 4515480446.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 4515480446 = 2 ⋅2257740223.

It can be written as a sum of positive squares in only one way, i.e., 4172514025 + 2268331129 = 64595^2 + 47627^2 .

It is not an unprimeable number, because it can be changed into a prime (6440845157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1610211287 + ... + 1610211290.

Almost surely, 2^6440845154 is an apocalyptic number.

6440845154 is a deficient number, since it is larger than the sum of its proper divisors (3220422580).

6440845154 is a wasteful number, since it uses less digits than its factorization.

6440845154 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3220422579.

The product of its (nonzero) digits is 307200, while the sum is 41.

The square root of 6440845154 is about 80254.8762007643. The cubic root of 6440845154 is about 1860.5768775632.

The spelling of 6440845154 in words is "six billion, four hundred forty million, eight hundred forty-five thousand, one hundred fifty-four".