1856378401 has 4 divisors (see below), whose sum is σ = 1856864304. Its totient is φ = 1855892500.

The previous prime is 1856378357. The next prime is 1856378423. The reversal of 1856378401 is 1048736581.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1856378401 - 2¹⁵ = 1856345633 is a prime.

It is a super-2 number, since 2×1856378401² = 6892281535398633602, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1856378471) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 237175 + ... + 244876.

It is an arithmetic number, because the mean of its divisors is an integer number (464216076).

Almost surely, 2^1856378401 is an apocalyptic number.

It is an amenable number.

1856378401 is a deficient number, since it is larger than the sum of its proper divisors (485903).

1856378401 is an equidigital number, since it uses as much as digits as its factorization.

1856378401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 485902.

The product of its (nonzero) digits is 161280, while the sum is 43.

The square root of 1856378401 is about 43085.7099396076. The cubic root of 1856378401 is about 1229.0102423979.

The spelling of 1856378401 in words is "one billion, eight hundred fifty-six million, three hundred seventy-eight thousand, four hundred one".