61528321 has 8 divisors (see below), whose sum is σ = 66216744. Its totient is φ = 56958720.

The previous prime is 61528319. The next prime is 61528333. The reversal of 61528321 is 12382516.

It can be written as a sum of positive squares in 4 ways, for example, as 2852721 + 58675600 = 1689^2 + 7660^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 61528321 - 2¹ = 61528319 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 61528321.

It is not an unprimeable number, because it can be changed into a prime (61528391) 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, 28630 + ... + 30703.

It is an arithmetic number, because the mean of its divisors is an integer number (8277093).

Almost surely, 2^61528321 is an apocalyptic number.

61528321 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

It is an amenable number.

61528321 is a deficient number, since it is larger than the sum of its proper divisors (4688423).

61528321 is a wasteful number, since it uses less digits than its factorization.

61528321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59411.

The product of its digits is 2880, while the sum is 28.

The square root of 61528321 is about 7843.9990438551. Note that the first 3 decimals coincide. The cubic root of 61528321 is about 394.7829197639.

The spelling of 61528321 in words is "sixty-one million, five hundred twenty-eight thousand, three hundred twenty-one".