61621057 has 2 divisors, whose sum is σ = 61621058. Its totient is φ = 61621056.

The previous prime is 61621003. The next prime is 61621061. The reversal of 61621057 is 75012616.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55711296 + 5909761 = 7464^2 + 2431^2 .

It is a cyclic number.

It is not a de Polignac number, because 61621057 - 2²³ = 53232449 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (61621097) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30810528 + 30810529.

It is an arithmetic number, because the mean of its divisors is an integer number (30810529).

Almost surely, 2^61621057 is an apocalyptic number.

It is an amenable number.

61621057 is a deficient number, since it is larger than the sum of its proper divisors (1).

61621057 is an equidigital number, since it uses as much as digits as its factorization.

61621057 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2520, while the sum is 28.

The square root of 61621057 is about 7849.9080886339. The cubic root of 61621057 is about 394.9811602401.

The spelling of 61621057 in words is "sixty-one million, six hundred twenty-one thousand, fifty-seven".