1551648451 has 4 divisors (see below), whose sum is σ = 1605153600. Its totient is φ = 1498143304.

The previous prime is 1551648443. The next prime is 1551648473. The reversal of 1551648451 is 1548461551.

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 1551648451 - 2³ = 1551648443 is a prime.

It is a super-2 number, since 2×1551648451² = 4815225830981398802, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1551648431) 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, 26752531 + ... + 26752588.

It is an arithmetic number, because the mean of its divisors is an integer number (401288400).

Almost surely, 2^1551648451 is an apocalyptic number.

1551648451 is a deficient number, since it is larger than the sum of its proper divisors (53505149).

1551648451 is an equidigital number, since it uses as much as digits as its factorization.

1551648451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53505148.

The product of its digits is 96000, while the sum is 40.

The square root of 1551648451 is about 39390.9691553787. The cubic root of 1551648451 is about 1157.7046492875.

The spelling of 1551648451 in words is "one billion, five hundred fifty-one million, six hundred forty-eight thousand, four hundred fifty-one".