1861998471 has 12 divisors (see below), whose sum is σ = 2762244472. Its totient is φ = 1207782576.

The previous prime is 1861998451. The next prime is 1861998473. The reversal of 1861998471 is 1748991681.

1861998471 is a `hidden beast` number, since 1 + 86 + 1 + 9 + 98 + 471 = 666.

It is not a de Polignac number, because 1861998471 - 2¹⁹ = 1861474183 is a prime.

It is a super-3 number, since 3×1861998471³ (a number of 29 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1861998473) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2795461 + ... + 2796126.

Almost surely, 2^1861998471 is an apocalyptic number.

1861998471 is a deficient number, since it is larger than the sum of its proper divisors (900246001).

1861998471 is a wasteful number, since it uses less digits than its factorization.

1861998471 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5591630 (or 5591627 counting only the distinct ones).

The product of its digits is 870912, while the sum is 54.

The square root of 1861998471 is about 43150.8803038826. The cubic root of 1861998471 is about 1230.2492435616.

The spelling of 1861998471 in words is "one billion, eight hundred sixty-one million, nine hundred ninety-eight thousand, four hundred seventy-one".