981642240 has 308 divisors, whose sum is σ = 3543995664. Its totient is φ = 260775936.

The previous prime is 981642223. The next prime is 981642241. The reversal of 981642240 is 42246189.

981642240 is a `hidden beast` number, since 9 + 8 + 1 + 642 + 2 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 981642195 and 981642204.

It is not an unprimeable number, because it can be changed into a prime (981642241) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 3732349 + ... + 3732611.

Almost surely, 2^981642240 is an apocalyptic number.

981642240 is a gapful number since it is divisible by the number (90) 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 981642240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1771997832).

981642240 is an abundant number, since it is smaller than the sum of its proper divisors (2562353424).

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

981642240 is an equidigital number, since it uses as much as digits as its factorization.

981642240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 306 (or 273 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 981642240 is about 31331.1704218020. The cubic root of 981642240 is about 993.8429147726.

The spelling of 981642240 in words is "nine hundred eighty-one million, six hundred forty-two thousand, two hundred forty".