1820862157 has 4 divisors (see below), whose sum is σ = 1820947996. Its totient is φ = 1820776320.

The previous prime is 1820862151. The next prime is 1820862209. The reversal of 1820862157 is 7512680281.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 1428386436 + 392475721 = 37794^2 + 19811^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1820862157 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1820862151) 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, 14557 + ... + 62077.

It is an arithmetic number, because the mean of its divisors is an integer number (455236999).

Almost surely, 2^1820862157 is an apocalyptic number.

It is an amenable number.

1820862157 is a deficient number, since it is larger than the sum of its proper divisors (85839).

1820862157 is an equidigital number, since it uses as much as digits as its factorization.

1820862157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85838.

The product of its (nonzero) digits is 53760, while the sum is 40.

The square root of 1820862157 is about 42671.5614549081. The cubic root of 1820862157 is about 1221.1219091683.

The spelling of 1820862157 in words is "one billion, eight hundred twenty million, eight hundred sixty-two thousand, one hundred fifty-seven".