29688911521 has 2 divisors, whose sum is σ = 29688911522. Its totient is φ = 29688911520.

The previous prime is 29688911489. The next prime is 29688911531. The reversal of 29688911521 is 12511988692.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21269013921 + 8419897600 = 145839^2 + 91760^2 .

It is a cyclic number.

It is not a de Polignac number, because 29688911521 - 2⁵ = 29688911489 is a prime.

It is not a weakly prime, because it can be changed into another prime (29688911531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14844455760 + 14844455761.

It is an arithmetic number, because the mean of its divisors is an integer number (14844455761).

Almost surely, 2^29688911521 is an apocalyptic number.

It is an amenable number.

29688911521 is a deficient number, since it is larger than the sum of its proper divisors (1).

29688911521 is an equidigital number, since it uses as much as digits as its factorization.

29688911521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 622080, while the sum is 52.

The spelling of 29688911521 in words is "twenty-nine billion, six hundred eighty-eight million, nine hundred eleven thousand, five hundred twenty-one".