61228381 has 2 divisors, whose sum is σ = 61228382. Its totient is φ = 61228380.

The previous prime is 61228361. The next prime is 61228399. The reversal of 61228381 is 18382216.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 60295225 + 933156 = 7765^2 + 966^2 .

It is a cyclic number.

It is not a de Polignac number, because 61228381 - 2⁹ = 61227869 is a prime.

It is a super-2 number, since 2×61228381² = 7497829279762322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61228301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30614190 + 30614191.

It is an arithmetic number, because the mean of its divisors is an integer number (30614191).

Almost surely, 2^61228381 is an apocalyptic number.

It is an amenable number.

61228381 is a deficient number, since it is larger than the sum of its proper divisors (1).

61228381 is an equidigital number, since it uses as much as digits as its factorization.

61228381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4608, while the sum is 31.

The square root of 61228381 is about 7824.8566121048. The cubic root of 61228381 is about 394.1403748825.

The spelling of 61228381 in words is "sixty-one million, two hundred twenty-eight thousand, three hundred eighty-one".