218442947631 has 8 divisors (see below), whose sum is σ = 291272332080. Its totient is φ = 145621097472.

The previous prime is 218442947621. The next prime is 218442947683. The reversal of 218442947631 is 136749244812.

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

It is not a de Polignac number, because 218442947631 - 2¹⁰ = 218442946607 is a prime.

It is a super-2 number, since 2×218442947631² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218442947621) 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, 1815570 + ... + 1932143.

It is an arithmetic number, because the mean of its divisors is an integer number (36409041510).

Almost surely, 2^218442947631 is an apocalyptic number.

218442947631 is a deficient number, since it is larger than the sum of its proper divisors (72829384449).

218442947631 is a wasteful number, since it uses less digits than its factorization.

218442947631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3767145.

The product of its digits is 2322432, while the sum is 51.

The spelling of 218442947631 in words is "two hundred eighteen billion, four hundred forty-two million, nine hundred forty-seven thousand, six hundred thirty-one".