25195921819 has 4 divisors (see below), whose sum is σ = 25196491080. Its totient is φ = 25195352560.

The previous prime is 25195921771. The next prime is 25195921837. The reversal of 25195921819 is 91812959152.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 25195921819 - 2²⁷ = 25061704091 is a prime.

It is a super-2 number, since 2×25195921819² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25195921879) 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, 212074 + ... + 308815.

It is an arithmetic number, because the mean of its divisors is an integer number (6299122770).

Almost surely, 2^25195921819 is an apocalyptic number.

25195921819 is a deficient number, since it is larger than the sum of its proper divisors (569261).

25195921819 is an equidigital number, since it uses as much as digits as its factorization.

25195921819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 569260.

The product of its digits is 583200, while the sum is 52.

The spelling of 25195921819 in words is "twenty-five billion, one hundred ninety-five million, nine hundred twenty-one thousand, eight hundred nineteen".