61400813 has 2 divisors, whose sum is σ = 61400814. Its totient is φ = 61400812.

The previous prime is 61400809. The next prime is 61400819. The reversal of 61400813 is 31800416.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 58782889 + 2617924 = 7667^2 + 1618^2 .

It is a cyclic number.

It is not a de Polignac number, because 61400813 - 2² = 61400809 is a prime.

61400813 is a modest number, since divided by 813 gives 614 as remainder.

It is equal to p_3640244 and since 61400813 and 3640244 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61400819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30700406 + 30700407.

It is an arithmetic number, because the mean of its divisors is an integer number (30700407).

Almost surely, 2^61400813 is an apocalyptic number.

It is an amenable number.

61400813 is a deficient number, since it is larger than the sum of its proper divisors (1).

61400813 is an equidigital number, since it uses as much as digits as its factorization.

61400813 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 61400813 is about 7835.8670866727. The cubic root of 61400813 is about 394.5100221650.

The spelling of 61400813 in words is "sixty-one million, four hundred thousand, eight hundred thirteen".