15515651551 has 2 divisors, whose sum is σ = 15515651552. Its totient is φ = 15515651550.

The previous prime is 15515651539. The next prime is 15515651611.

It is a happy number.

15515651551 is nontrivially palindromic in base 10.

It is a weak prime.

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 15515651551 - 2¹¹ = 15515649503 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15515651251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7757825775 + 7757825776.

It is an arithmetic number, because the mean of its divisors is an integer number (7757825776).

Almost surely, 2^15515651551 is an apocalyptic number.

15515651551 is a deficient number, since it is larger than the sum of its proper divisors (1).

15515651551 is an equidigital number, since it uses as much as digits as its factorization.

15515651551 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 93750, while the sum is 40.

The spelling of 15515651551 in words is "fifteen billion, five hundred fifteen million, six hundred fifty-one thousand, five hundred fifty-one".