155661212 has 48 divisors (see below), whose sum is σ = 328224960. Its totient is φ = 63178752.

The previous prime is 155661211. The next prime is 155661269. The reversal of 155661212 is 212166551.

It is a happy number.

155661212 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155661211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 41228 + ... + 44844.

It is an arithmetic number, because the mean of its divisors is an integer number (6838020).

Almost surely, 2^155661212 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 155661212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (164112480).

155661212 is an abundant number, since it is smaller than the sum of its proper divisors (172563748).

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

155661212 is a wasteful number, since it uses less digits than its factorization.

155661212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3710 (or 3708 counting only the distinct ones).

The product of its digits is 3600, while the sum is 29.

The square root of 155661212 is about 12476.4262511346. The cubic root of 155661212 is about 537.9312847844.

The spelling of 155661212 in words is "one hundred fifty-five million, six hundred sixty-one thousand, two hundred twelve".