1553663551 has 4 divisors (see below), whose sum is σ = 1694905704. Its totient is φ = 1412421400.

The previous prime is 1553663519. The next prime is 1553663557.

It is a happy number.

1553663551 is nontrivially palindromic in base 10.

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 1553663551 - 2⁵ = 1553663519 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1553663557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 70621060 + ... + 70621081.

It is an arithmetic number, because the mean of its divisors is an integer number (423726426).

Almost surely, 2^1553663551 is an apocalyptic number.

1553663551 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1553663551 is a deficient number, since it is larger than the sum of its proper divisors (141242153).

1553663551 is a wasteful number, since it uses less digits than its factorization.

1553663551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141242152.

The product of its digits is 202500, while the sum is 40.

The square root of 1553663551 is about 39416.5390540570. The cubic root of 1553663551 is about 1158.2055964082.

The spelling of 1553663551 in words is "one billion, five hundred fifty-three million, six hundred sixty-three thousand, five hundred fifty-one".