1553541421 has 2 divisors, whose sum is σ = 1553541422. Its totient is φ = 1553541420.

The previous prime is 1553541419. The next prime is 1553541439. The reversal of 1553541421 is 1241453551.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 818589321 + 734952100 = 28611^2 + 27110^2 .

It is a cyclic number.

It is not a de Polignac number, because 1553541421 - 2¹ = 1553541419 is a prime.

Together with 1553541419, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1553541401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 776770710 + 776770711.

It is an arithmetic number, because the mean of its divisors is an integer number (776770711).

Almost surely, 2^1553541421 is an apocalyptic number.

It is an amenable number.

1553541421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1553541421 is an equidigital number, since it uses as much as digits as its factorization.

1553541421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12000, while the sum is 31.

The square root of 1553541421 is about 39414.9898008359. The cubic root of 1553541421 is about 1158.1752476333.

Adding to 1553541421 its reverse (1241453551), we get a palindrome (2794994972).

The spelling of 1553541421 in words is "one billion, five hundred fifty-three million, five hundred forty-one thousand, four hundred twenty-one".