61575421 has 2 divisors, whose sum is σ = 61575422. Its totient is φ = 61575420.

The previous prime is 61575407. The next prime is 61575431. The reversal of 61575421 is 12457516.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 57927321 + 3648100 = 7611^2 + 1910^2 .

It is a cyclic number.

It is not a de Polignac number, because 61575421 - 2¹⁷ = 61444349 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61575431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30787710 + 30787711.

It is an arithmetic number, because the mean of its divisors is an integer number (30787711).

Almost surely, 2^61575421 is an apocalyptic number.

It is an amenable number.

61575421 is a deficient number, since it is larger than the sum of its proper divisors (1).

61575421 is an equidigital number, since it uses as much as digits as its factorization.

61575421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8400, while the sum is 31.

The square root of 61575421 is about 7847.0007646234. Note that the first 3 decimals coincide. The cubic root of 61575421 is about 394.8836296624.

The spelling of 61575421 in words is "sixty-one million, five hundred seventy-five thousand, four hundred twenty-one".