661272 has 32 divisors (see below), whose sum is σ = 1684800. Its totient is φ = 216224.

The previous prime is 661267. The next prime is 661321. The reversal of 661272 is 272166.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1183 + ... + 1649.

It is an arithmetic number, because the mean of its divisors is an integer number (52650).

2⁶⁶¹²⁷² 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 661272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (842400).

661272 is an abundant number, since it is smaller than the sum of its proper divisors (1023528).

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

661272 is a wasteful number, since it uses less digits than its factorization.

661272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 535 (or 531 counting only the distinct ones).

The product of its digits is 1008, while the sum is 24.

The square root of 661272 is about 813.1863255122. The cubic root of 661272 is about 87.1217742473.

The spelling of 661272 in words is "six hundred sixty-one thousand, two hundred seventy-two".