15551144381 has 2 divisors, whose sum is σ = 15551144382. Its totient is φ = 15551144380.

The previous prime is 15551144359. The next prime is 15551144419. The reversal of 15551144381 is 18344115551.

It is an a-pointer prime, because the next prime (15551144419) can be obtained adding 15551144381 to its sum of digits (38).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11133415225 + 4417729156 = 105515^2 + 66466^2 .

It is a cyclic number.

It is not a de Polignac number, because 15551144381 - 2¹⁰ = 15551143357 is a prime.

It is a super-2 number, since 2×15551144381² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15551144311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7775572190 + 7775572191.

It is an arithmetic number, because the mean of its divisors is an integer number (7775572191).

Almost surely, 2^15551144381 is an apocalyptic number.

It is an amenable number.

15551144381 is a deficient number, since it is larger than the sum of its proper divisors (1).

15551144381 is an equidigital number, since it uses as much as digits as its factorization.

15551144381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48000, while the sum is 38.

The spelling of 15551144381 in words is "fifteen billion, five hundred fifty-one million, one hundred forty-four thousand, three hundred eighty-one".