1249809536 has 64 divisors (see below), whose sum is σ = 2686306680. Its totient is φ = 576995328.

The previous prime is 1249809529. The next prime is 1249809559. The reversal of 1249809536 is 6359089421.

It can be written as a sum of positive squares in 4 ways, for example, as 1152195136 + 97614400 = 33944^2 + 9880^2 .

It is a tau number, because it is divible by the number of its divisors (64).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 109910 + ... + 120746.

Almost surely, 2^1249809536 is an apocalyptic number.

1249809536 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1249809536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1343153340).

1249809536 is an abundant number, since it is smaller than the sum of its proper divisors (1436497144).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1249809536 is a wasteful number, since it uses less digits than its factorization.

1249809536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10921 (or 10909 counting only the distinct ones).

The product of its (nonzero) digits is 466560, while the sum is 47.

The square root of 1249809536 is about 35352.6453889946. The cubic root of 1249809536 is about 1077.1626299370.

The spelling of 1249809536 in words is "one billion, two hundred forty-nine million, eight hundred nine thousand, five hundred thirty-six".