61810321 has 2 divisors, whose sum is σ = 61810322. Its totient is φ = 61810320.

The previous prime is 61810297. The next prime is 61810327. The reversal of 61810321 is 12301816.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 59120721 + 2689600 = 7689^2 + 1640^2 .

It is a cyclic number.

It is not a de Polignac number, because 61810321 - 2⁵ = 61810289 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a junction number, because it is equal to n+sod(n) for n = 61810292 and 61810301.

It is not a weakly prime, because it can be changed into another prime (61810327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30905160 + 30905161.

It is an arithmetic number, because the mean of its divisors is an integer number (30905161).

Almost surely, 2^61810321 is an apocalyptic number.

It is an amenable number.

61810321 is a deficient number, since it is larger than the sum of its proper divisors (1).

61810321 is an equidigital number, since it uses as much as digits as its factorization.

61810321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 61810321 is about 7861.9540191990. The cubic root of 61810321 is about 395.3851309656.

The spelling of 61810321 in words is "sixty-one million, eight hundred ten thousand, three hundred twenty-one".