78156537212 has 36 divisors (see below), whose sum is σ = 147851730936. Its totient is φ = 35936420160.

The previous prime is 78156537211. The next prime is 78156537247. The reversal of 78156537212 is 21273565187.

It is a super-2 number, since 2×78156537212² (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 (78156537211) 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, 3752387 + ... + 3773157.

It is an arithmetic number, because the mean of its divisors is an integer number (4106992526).

Almost surely, 2^78156537212 is an apocalyptic number.

It is an amenable number.

78156537212 is a deficient number, since it is larger than the sum of its proper divisors (69695193724).

78156537212 is a wasteful number, since it uses less digits than its factorization.

78156537212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21326 (or 21055 counting only the distinct ones).

The product of its digits is 705600, while the sum is 47.

The spelling of 78156537212 in words is "seventy-eight billion, one hundred fifty-six million, five hundred thirty-seven thousand, two hundred twelve".