1891400340 has 48 divisors (see below), whose sum is σ = 5299564032. Its totient is φ = 504026496.

The previous prime is 1891400339. The next prime is 1891400341. The reversal of 1891400340 is 430041981.

It is a happy number.

1891400340 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (1891400339) and next prime (1891400341).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 1891400298 and 1891400307.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1891400341) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 83962 + ... + 104078.

It is an arithmetic number, because the mean of its divisors is an integer number (110407584).

Almost surely, 2^1891400340 is an apocalyptic number.

1891400340 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1891400340 is an abundant number, since it is smaller than the sum of its proper divisors (3408163692).

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

1891400340 is a wasteful number, since it uses less digits than its factorization.

1891400340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21696 (or 21694 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 1891400340 is about 43490.2326965492. The cubic root of 1891400340 is about 1236.6908690912.

The spelling of 1891400340 in words is "one billion, eight hundred ninety-one million, four hundred thousand, three hundred forty".