1218972731040 has 72 divisors (see below), whose sum is σ = 4159744449588. Its totient is φ = 325059394560.

The previous prime is 1218972731033. The next prime is 1218972731057. The reversal of 1218972731040 is 401372798121.

It can be written as a sum of positive squares in 2 ways, for example, as 1194745185936 + 24227545104 = 1093044^2 + 155652^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 423252981 + ... + 423255860.

Almost surely, 2^{1218972731040} is an apocalyptic number.

1218972731040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1218972731040 is an abundant number, since it is smaller than the sum of its proper divisors (2940771718548).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1218972731040 is a wasteful number, since it uses less digits than its factorization.

1218972731040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 846508862 (or 846508851 counting only the distinct ones).

The product of its (nonzero) digits is 169344, while the sum is 45.

The spelling of 1218972731040 in words is "one trillion, two hundred eighteen billion, nine hundred seventy-two million, seven hundred thirty-one thousand, forty".