1851221018210 has 16 divisors (see below), whose sum is σ = 3334263700536. Its totient is φ = 740029325568.

The previous prime is 1851221018203. The next prime is 1851221018219. The reversal of 1851221018210 is 128101221581.

It can be written as a sum of positive squares in 4 ways, for example, as 1345189391329 + 506031626881 = 1159823^2 + 711359^2 .

It is not an unprimeable number, because it can be changed into a prime (1851221018219) 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, 57368279 + ... + 57400538.

Almost surely, 2^{1851221018210} is an apocalyptic number.

1851221018210 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1851221018210 is a deficient number, since it is larger than the sum of its proper divisors (1483042682326).

1851221018210 is a wasteful number, since it uses less digits than its factorization.

1851221018210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114770437.

The product of its (nonzero) digits is 2560, while the sum is 32.

Adding to 1851221018210 its reverse (128101221581), we get a palindrome (1979322239791).

The spelling of 1851221018210 in words is "one trillion, eight hundred fifty-one billion, two hundred twenty-one million, eighteen thousand, two hundred ten".