1891434240 has 252 divisors, whose sum is σ = 6796107864. Its totient is φ = 504133632.

The previous prime is 1891434239. The next prime is 1891434269. The reversal of 1891434240 is 424341981.

It is a happy number.

1891434240 is a `hidden beast` number, since 189 + 1 + 434 + 2 + 40 = 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 = 1891434195 and 1891434204.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 932107 + ... + 934133.

It is an arithmetic number, because the mean of its divisors is an integer number (26968682).

Almost surely, 2^1891434240 is an apocalyptic number.

1891434240 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 1891434240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3398053932).

1891434240 is an abundant number, since it is smaller than the sum of its proper divisors (4904673624).

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

1891434240 is an frugal number, since it uses more digits than its factorization.

1891434240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2066 (or 2037 counting only the distinct ones).

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

The square root of 1891434240 is about 43490.6224374865. The cubic root of 1891434240 is about 1236.6982575446.

The spelling of 1891434240 in words is "one billion, eight hundred ninety-one million, four hundred thirty-four thousand, two hundred forty".