1866820157 has 8 divisors (see below), whose sum is σ = 1876089600. Its totient is φ = 1857563344.

The previous prime is 1866820127. The next prime is 1866820181. The reversal of 1866820157 is 7510286681.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1866820157 - 2¹⁰ = 1866819133 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 (1866820127) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 439319 + ... + 443547.

It is an arithmetic number, because the mean of its divisors is an integer number (234511200).

Almost surely, 2^1866820157 is an apocalyptic number.

It is an amenable number.

1866820157 is a deficient number, since it is larger than the sum of its proper divisors (9269443).

1866820157 is a wasteful number, since it uses less digits than its factorization.

1866820157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6315.

The product of its (nonzero) digits is 161280, while the sum is 44.

The square root of 1866820157 is about 43206.7142583187. The cubic root of 1866820157 is about 1231.3102474165.

The spelling of 1866820157 in words is "one billion, eight hundred sixty-six million, eight hundred twenty thousand, one hundred fifty-seven".