15155545421 has 2 divisors, whose sum is σ = 15155545422. Its totient is φ = 15155545420.

The previous prime is 15155545357. The next prime is 15155545463. The reversal of 15155545421 is 12454555151.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9897265225 + 5258280196 = 99485^2 + 72514^2 .

It is a cyclic number.

It is not a de Polignac number, because 15155545421 - 2⁶ = 15155545357 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15155545121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7577772710 + 7577772711.

It is an arithmetic number, because the mean of its divisors is an integer number (7577772711).

Almost surely, 2^15155545421 is an apocalyptic number.

It is an amenable number.

15155545421 is a deficient number, since it is larger than the sum of its proper divisors (1).

15155545421 is an equidigital number, since it uses as much as digits as its factorization.

15155545421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 100000, while the sum is 38.

The spelling of 15155545421 in words is "fifteen billion, one hundred fifty-five million, five hundred forty-five thousand, four hundred twenty-one".