6645249987 has 8 divisors (see below), whose sum is σ = 9099801936. Its totient is φ = 4310432352.

The previous prime is 6645249973. The next prime is 6645249991. The reversal of 6645249987 is 7899425466.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 6645249987 - 2⁷ = 6645249859 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6645249987.

It is not an unprimeable number, because it can be changed into a prime (6645249917) 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 7 ways as a sum of consecutive naturals, for example, 29933448 + ... + 29933669.

It is an arithmetic number, because the mean of its divisors is an integer number (1137475242).

Almost surely, 2^6645249987 is an apocalyptic number.

6645249987 is a deficient number, since it is larger than the sum of its proper divisors (2454551949).

6645249987 is a wasteful number, since it uses less digits than its factorization.

6645249987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59867157.

The product of its digits is 26127360, while the sum is 60.

The square root of 6645249987 is about 81518.4027505446. The cubic root of 6645249987 is about 1880.0545090390.

The spelling of 6645249987 in words is "six billion, six hundred forty-five million, two hundred forty-nine thousand, nine hundred eighty-seven".