21025401407 has 2 divisors, whose sum is σ = 21025401408. Its totient is φ = 21025401406.

The previous prime is 21025401337. The next prime is 21025401409. The reversal of 21025401407 is 70410452012.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21025401407 is a prime.

Together with 21025401409, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21025401409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10512700703 + 10512700704.

It is an arithmetic number, because the mean of its divisors is an integer number (10512700704).

Almost surely, 2^21025401407 is an apocalyptic number.

21025401407 is a deficient number, since it is larger than the sum of its proper divisors (1).

21025401407 is an equidigital number, since it uses as much as digits as its factorization.

21025401407 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2240, while the sum is 26.

Adding to 21025401407 its reverse (70410452012), we get a palindrome (91435853419).

The spelling of 21025401407 in words is "twenty-one billion, twenty-five million, four hundred one thousand, four hundred seven".