1994744640 has 448 divisors, whose sum is σ = 8075980800. Its totient is φ = 406093824.

The previous prime is 1994744639. The next prime is 1994744641. The reversal of 1994744640 is 464474991.

It is an interprime number because it is at equal distance from previous prime (1994744639) and next prime (1994744641).

It is a tau number, because it is divible by the number of its divisors (448).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 1994744640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1994744641) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2170101 + ... + 2171019.

Almost surely, 2^1994744640 is an apocalyptic number.

1994744640 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 1994744640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4037990400).

1994744640 is an abundant number, since it is smaller than the sum of its proper divisors (6081236160).

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

1994744640 is a wasteful number, since it uses less digits than its factorization.

1994744640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 982 (or 972 counting only the distinct ones).

The product of its (nonzero) digits is 870912, while the sum is 48.

The square root of 1994744640 is about 44662.5641897104. The cubic root of 1994744640 is about 1258.8165254355.

The spelling of 1994744640 in words is "one billion, nine hundred ninety-four million, seven hundred forty-four thousand, six hundred forty".