1212211009956 has 24 divisors (see below), whose sum is σ = 2864296059520. Its totient is φ = 398955521952.

The previous prime is 1212211009943. The next prime is 1212211009957. The reversal of 1212211009956 is 6599001122121.

It is a happy number.

It is a super-2 number, since 2×1212211009956² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1212211009957) 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, 639350851 + ... + 639352746.

Almost surely, 2^{1212211009956} is an apocalyptic number.

It is an amenable number.

1212211009956 is an abundant number, since it is smaller than the sum of its proper divisors (1652085049564).

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

1212211009956 is a wasteful number, since it uses less digits than its factorization.

1212211009956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1278703683 (or 1278703681 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 39.

The spelling of 1212211009956 in words is "one trillion, two hundred twelve billion, two hundred eleven million, nine thousand, nine hundred fifty-six".