1209961536 has 112 divisors (see below), whose sum is σ = 3873983616. Its totient is φ = 325361664.

The previous prime is 1209961471. The next prime is 1209961559. The reversal of 1209961536 is 6351699021.

It is a tau number, because it is divible by the number of its divisors (112).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3631 + ... + 49326.

Almost surely, 2^1209961536 is an apocalyptic number.

1209961536 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 1209961536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1936991808).

1209961536 is an abundant number, since it is smaller than the sum of its proper divisors (2664022080).

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

1209961536 is a wasteful number, since it uses less digits than its factorization.

1209961536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52996 (or 52986 counting only the distinct ones).

The product of its (nonzero) digits is 87480, while the sum is 42.

The square root of 1209961536 is about 34784.5013763314. The cubic root of 1209961536 is about 1065.5909453730.

The spelling of 1209961536 in words is "one billion, two hundred nine million, nine hundred sixty-one thousand, five hundred thirty-six".