1553240251 has 4 divisors (see below), whose sum is σ = 1572901600. Its totient is φ = 1533578904.

The previous prime is 1553240239. The next prime is 1553240323. The reversal of 1553240251 is 1520423551.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1553240251 - 2¹⁷ = 1553109179 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1553240201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9830556 + ... + 9830713.

It is an arithmetic number, because the mean of its divisors is an integer number (393225400).

Almost surely, 2^1553240251 is an apocalyptic number.

1553240251 is a deficient number, since it is larger than the sum of its proper divisors (19661349).

1553240251 is an equidigital number, since it uses as much as digits as its factorization.

1553240251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19661348.

The product of its (nonzero) digits is 6000, while the sum is 28.

The square root of 1553240251 is about 39411.1691148588. The cubic root of 1553240251 is about 1158.1004013977.

The spelling of 1553240251 in words is "one billion, five hundred fifty-three million, two hundred forty thousand, two hundred fifty-one".