1541551421 has 2 divisors, whose sum is σ = 1541551422. Its totient is φ = 1541551420.

The previous prime is 1541551393. The next prime is 1541551433. The reversal of 1541551421 is 1241551451.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1203396100 + 338155321 = 34690^2 + 18389^2 .

It is a cyclic number.

It is not a de Polignac number, because 1541551421 - 2¹⁰ = 1541550397 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1541556421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 770775710 + 770775711.

It is an arithmetic number, because the mean of its divisors is an integer number (770775711).

Almost surely, 2^1541551421 is an apocalyptic number.

It is an amenable number.

1541551421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1541551421 is an equidigital number, since it uses as much as digits as its factorization.

1541551421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4000, while the sum is 29.

The square root of 1541551421 is about 39262.5956987054. The cubic root of 1541551421 is about 1155.1880083495.

The spelling of 1541551421 in words is "one billion, five hundred forty-one million, five hundred fifty-one thousand, four hundred twenty-one".