1242646640 has 80 divisors (see below), whose sum is σ = 2936062080. Its totient is φ = 489058560.

The previous prime is 1242646633. The next prime is 1242646651. The reversal of 1242646640 is 466462421.

It is a tau number, because it is divible by the number of its divisors (80).

It is a self number, because there is not a number n which added to its sum of digits gives 1242646640.

It is a congruent number.

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, 1531835 + ... + 1532645.

It is an arithmetic number, because the mean of its divisors is an integer number (36700776).

Almost surely, 2^1242646640 is an apocalyptic number.

1242646640 is a gapful number since it is divisible by the number (10) 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 1242646640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1468031040).

1242646640 is an abundant number, since it is smaller than the sum of its proper divisors (1693415440).

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

1242646640 is a wasteful number, since it uses less digits than its factorization.

1242646640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1110 (or 1104 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 35.

The square root of 1242646640 is about 35251.1934549740. The cubic root of 1242646640 is about 1075.1008782203.

The spelling of 1242646640 in words is "one billion, two hundred forty-two million, six hundred forty-six thousand, six hundred forty".