1640547625405 has 8 divisors (see below), whose sum is σ = 2120092315992. Its totient is φ = 1211481323328.

The previous prime is 1640547625391. The next prime is 1640547625429. The reversal of 1640547625405 is 5045267450461.

It can be written as a sum of positive squares in 4 ways, for example, as 35818590564 + 1604729034841 = 189258^2 + 1266779^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1640547625405 - 2⁵ = 1640547625373 is a prime.

It is a super-2 number, since 2×1640547625405² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12619597054 + ... + 12619597183.

It is an arithmetic number, because the mean of its divisors is an integer number (265011539499).

Almost surely, 2^{1640547625405} is an apocalyptic number.

It is an amenable number.

1640547625405 is a deficient number, since it is larger than the sum of its proper divisors (479544690587).

1640547625405 is a wasteful number, since it uses less digits than its factorization.

1640547625405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25239194255.

The product of its (nonzero) digits is 4032000, while the sum is 49.

The spelling of 1640547625405 in words is "one trillion, six hundred forty billion, five hundred forty-seven million, six hundred twenty-five thousand, four hundred five".