25378999993 has 2 divisors, whose sum is σ = 25378999994. Its totient is φ = 25378999992.

The previous prime is 25378999973. The next prime is 25379000027. The reversal of 25378999993 is 39999987352.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14499049744 + 10879950249 = 120412^2 + 104307^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25378999993 is a prime.

It is not a weakly prime, because it can be changed into another prime (25378999973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12689499996 + 12689499997.

It is an arithmetic number, because the mean of its divisors is an integer number (12689499997).

Almost surely, 2^25378999993 is an apocalyptic number.

It is an amenable number.

25378999993 is a deficient number, since it is larger than the sum of its proper divisors (1).

25378999993 is an equidigital number, since it uses as much as digits as its factorization.

25378999993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 297606960, while the sum is 73.

The spelling of 25378999993 in words is "twenty-five billion, three hundred seventy-eight million, nine hundred ninety-nine thousand, nine hundred ninety-three".