1851656040 has 192 divisors, whose sum is σ = 6690378240. Its totient is φ = 441054720.

The previous prime is 1851656021. The next prime is 1851656069. The reversal of 1851656040 is 406561581.

1851656040 is a `hidden beast` number, since 1 + 8 + 51 + 6 + 560 + 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 = 1851655986 and 1851656004.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 138699 + ... + 151461.

It is an arithmetic number, because the mean of its divisors is an integer number (34845720).

Almost surely, 2^1851656040 is an apocalyptic number.

1851656040 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 1851656040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3345189120).

1851656040 is an abundant number, since it is smaller than the sum of its proper divisors (4838722200).

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

1851656040 is a wasteful number, since it uses less digits than its factorization.

1851656040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12824 (or 12817 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

The square root of 1851656040 is about 43030.8731029246. The cubic root of 1851656040 is about 1227.9672153994.

The spelling of 1851656040 in words is "one billion, eight hundred fifty-one million, six hundred fifty-six thousand, forty".