6440154760516 has 81 divisors (see below), whose sum is σ = 11660794544581. Its totient is φ = 3112210486528.

The previous prime is 6440154760511. The next prime is 6440154760603. The reversal of 6440154760516 is 6150674510446.

The square root of 6440154760516 is 2537746.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 13 ways, for example, as 6283895832900 + 156258927616 = 2506770^2 + 395296^2 .

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6440154760516.

It is not an unprimeable number, because it can be changed into a prime (6440154760511) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 23941095630 + ... + 23941095898.

Almost surely, 2^{6440154760516} is an apocalyptic number.

6440154760516 is the 2537746-th square number.

It is an amenable number.

6440154760516 is a deficient number, since it is larger than the sum of its proper divisors (5220639784065).

6440154760516 is an frugal number, since it uses more digits than its factorization.

6440154760516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 826 (or 413 counting only the distinct ones).

The product of its (nonzero) digits is 2419200, while the sum is 49.

Multiplying 6440154760516 by its sum of digits (49), we get a square (315567583265284 = 17764222²).

The spelling of 6440154760516 in words is "six trillion, four hundred forty billion, one hundred fifty-four million, seven hundred sixty thousand, five hundred sixteen".