1242555451 has 4 divisors (see below), whose sum is σ = 1260056304. Its totient is φ = 1225054600.

The previous prime is 1242555443. The next prime is 1242555463. The reversal of 1242555451 is 1545552421.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1545552421 = 7 ⋅220793203.

It is a cyclic number.

It is not a de Polignac number, because 1242555451 - 2³ = 1242555443 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1242555481) 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, 8750320 + ... + 8750461.

It is an arithmetic number, because the mean of its divisors is an integer number (315014076).

Almost surely, 2^1242555451 is an apocalyptic number.

1242555451 is a deficient number, since it is larger than the sum of its proper divisors (17500853).

1242555451 is an equidigital number, since it uses as much as digits as its factorization.

1242555451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17500852.

The product of its digits is 40000, while the sum is 34.

The square root of 1242555451 is about 35249.9000140426. The cubic root of 1242555451 is about 1075.0745795743.

It can be divided in two parts, 12425 and 55451, that added together give a palindrome (67876).

The spelling of 1242555451 in words is "one billion, two hundred forty-two million, five hundred fifty-five thousand, four hundred fifty-one".