5515121021551 has 2 divisors, whose sum is σ = 5515121021552. Its totient is φ = 5515121021550.

The previous prime is 5515121021549. The next prime is 5515121021567. The reversal of 5515121021551 is 1551201215155.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 5515121021551 - 2¹ = 5515121021549 is a prime.

Together with 5515121021549, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (5515121021581) 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, 2757560510775 + 2757560510776.

It is an arithmetic number, because the mean of its divisors is an integer number (2757560510776).

Almost surely, 2^{5515121021551} is an apocalyptic number.

5515121021551 is a deficient number, since it is larger than the sum of its proper divisors (1).

5515121021551 is an equidigital number, since it uses as much as digits as its factorization.

5515121021551 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12500, while the sum is 34.

The spelling of 5515121021551 in words is "five trillion, five hundred fifteen billion, one hundred twenty-one million, twenty-one thousand, five hundred fifty-one".