20425641251 has 4 divisors (see below), whose sum is σ = 20426059392. Its totient is φ = 20425223112.

The previous prime is 20425641241. The next prime is 20425641263. The reversal of 20425641251 is 15214652402.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15214652402 = 2 ⋅7607326201.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20425641251 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20425641241) 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, 124355 + ... + 237308.

It is an arithmetic number, because the mean of its divisors is an integer number (5106514848).

Almost surely, 2^20425641251 is an apocalyptic number.

20425641251 is a deficient number, since it is larger than the sum of its proper divisors (418141).

20425641251 is an equidigital number, since it uses as much as digits as its factorization.

20425641251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 418140.

The product of its (nonzero) digits is 19200, while the sum is 32.

The spelling of 20425641251 in words is "twenty billion, four hundred twenty-five million, six hundred forty-one thousand, two hundred fifty-one".