25406662042 has 4 divisors (see below), whose sum is σ = 38109993066. Its totient is φ = 12703331020.

The previous prime is 25406662007. The next prime is 25406662049. The reversal of 25406662042 is 24026660452.

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

It can be written as a sum of positive squares in only one way, i.e., 18610143561 + 6796518481 = 136419^2 + 82441^2 .

It is a super-2 number, since 2×25406662042² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 25406661992 and 25406662010.

It is not an unprimeable number, because it can be changed into a prime (25406662049) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6351665509 + ... + 6351665512.

Almost surely, 2^25406662042 is an apocalyptic number.

25406662042 is a deficient number, since it is larger than the sum of its proper divisors (12703331024).

25406662042 is a wasteful number, since it uses less digits than its factorization.

25406662042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12703331023.

The product of its (nonzero) digits is 138240, while the sum is 37.

The spelling of 25406662042 in words is "twenty-five billion, four hundred six million, six hundred sixty-two thousand, forty-two".