1925640551657 has 4 divisors (see below), whose sum is σ = 1992041950020. Its totient is φ = 1859239153296.

The previous prime is 1925640551617. The next prime is 1925640551669. The reversal of 1925640551657 is 7561550465291.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1516730181136 + 408910370521 = 1231556^2 + 639461^2 .

It is a cyclic number.

It is not a de Polignac number, because 1925640551657 - 2¹⁰ = 1925640550633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1925640551617) 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, 33200699138 + ... + 33200699195.

It is an arithmetic number, because the mean of its divisors is an integer number (498010487505).

Almost surely, 2^{1925640551657} is an apocalyptic number.

It is an amenable number.

1925640551657 is a deficient number, since it is larger than the sum of its proper divisors (66401398363).

1925640551657 is an equidigital number, since it uses as much as digits as its factorization.

1925640551657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66401398362.

The product of its (nonzero) digits is 11340000, while the sum is 56.

The spelling of 1925640551657 in words is "one trillion, nine hundred twenty-five billion, six hundred forty million, five hundred fifty-one thousand, six hundred fifty-seven".