61541621 has 2 divisors, whose sum is σ = 61541622. Its totient is φ = 61541620.

The previous prime is 61541617. The next prime is 61541647. The reversal of 61541621 is 12614516.

It is an a-pointer prime, because the next prime (61541647) can be obtained adding 61541621 to its sum of digits (26).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 61058596 + 483025 = 7814^2 + 695^2 .

It is a cyclic number.

It is not a de Polignac number, because 61541621 - 2² = 61541617 is a prime.

It is a super-2 number, since 2×61541621² = 7574742230615282, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61541611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30770810 + 30770811.

It is an arithmetic number, because the mean of its divisors is an integer number (30770811).

Almost surely, 2^61541621 is an apocalyptic number.

It is an amenable number.

61541621 is a deficient number, since it is larger than the sum of its proper divisors (1).

61541621 is an equidigital number, since it uses as much as digits as its factorization.

61541621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1440, while the sum is 26.

The square root of 61541621 is about 7844.8467798932. The cubic root of 61541621 is about 394.8113632214.

The spelling of 61541621 in words is "sixty-one million, five hundred forty-one thousand, six hundred twenty-one".