24691617421 has 2 divisors, whose sum is σ = 24691617422. Its totient is φ = 24691617420.

The previous prime is 24691617383. The next prime is 24691617437. The reversal of 24691617421 is 12471619642.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13592994921 + 11098622500 = 116589^2 + 105350^2 .

It is a cyclic number.

It is not a de Polignac number, because 24691617421 - 2¹¹ = 24691615373 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (24691617491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12345808710 + 12345808711.

It is an arithmetic number, because the mean of its divisors is an integer number (12345808711).

Almost surely, 2^24691617421 is an apocalyptic number.

It is an amenable number.

24691617421 is a deficient number, since it is larger than the sum of its proper divisors (1).

24691617421 is an equidigital number, since it uses as much as digits as its factorization.

24691617421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 145152, while the sum is 43.

The spelling of 24691617421 in words is "twenty-four billion, six hundred ninety-one million, six hundred seventeen thousand, four hundred twenty-one".