21251103403 has 2 divisors, whose sum is σ = 21251103404. Its totient is φ = 21251103402.

The previous prime is 21251103397. The next prime is 21251103409. The reversal of 21251103403 is 30430115212.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (21251103397) and next prime (21251103409).

It is a cyclic number.

It is not a de Polignac number, because 21251103403 - 2¹³ = 21251095211 is a prime.

It is not a weakly prime, because it can be changed into another prime (21251103409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10625551701 + 10625551702.

It is an arithmetic number, because the mean of its divisors is an integer number (10625551702).

Almost surely, 2^21251103403 is an apocalyptic number.

21251103403 is a deficient number, since it is larger than the sum of its proper divisors (1).

21251103403 is an equidigital number, since it uses as much as digits as its factorization.

21251103403 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 720, while the sum is 22.

Adding to 21251103403 its reverse (30430115212), we get a palindrome (51681218615).

The spelling of 21251103403 in words is "twenty-one billion, two hundred fifty-one million, one hundred three thousand, four hundred three".