15305642981 has 2 divisors, whose sum is σ = 15305642982. Its totient is φ = 15305642980.

The previous prime is 15305642959. The next prime is 15305643007. The reversal of 15305642981 is 18924650351.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14532302500 + 773340481 = 120550^2 + 27809^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15305642981 is a prime.

It is a super-2 number, since 2×15305642981² (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 (15305642281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7652821490 + 7652821491.

It is an arithmetic number, because the mean of its divisors is an integer number (7652821491).

Almost surely, 2^15305642981 is an apocalyptic number.

It is an amenable number.

15305642981 is a deficient number, since it is larger than the sum of its proper divisors (1).

15305642981 is an equidigital number, since it uses as much as digits as its factorization.

15305642981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 259200, while the sum is 44.

The spelling of 15305642981 in words is "fifteen billion, three hundred five million, six hundred forty-two thousand, nine hundred eighty-one".