1245543987 has 16 divisors (see below), whose sum is σ = 1707726080. Its totient is φ = 806918112.

The previous prime is 1245543973. The next prime is 1245543989. The reversal of 1245543987 is 7893455421.

It is not a de Polignac number, because 1245543987 - 2¹² = 1245539891 is a prime.

It is a Smith number, since the sum of its digits (48) 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 (1245543989) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 88818 + ... + 101880.

It is an arithmetic number, because the mean of its divisors is an integer number (106732880).

Almost surely, 2^1245543987 is an apocalyptic number.

1245543987 is a deficient number, since it is larger than the sum of its proper divisors (462182093).

1245543987 is a wasteful number, since it uses less digits than its factorization.

1245543987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13962.

The product of its digits is 1209600, while the sum is 48.

The square root of 1245543987 is about 35292.2652574187. The cubic root of 1245543987 is about 1075.9357957826.

The spelling of 1245543987 in words is "one billion, two hundred forty-five million, five hundred forty-three thousand, nine hundred eighty-seven".