61491401 has 2 divisors, whose sum is σ = 61491402. Its totient is φ = 61491400.

The previous prime is 61491389. The next prime is 61491413. The reversal of 61491401 is 10419416.

It is a balanced prime because it is at equal distance from previous prime (61491389) and next prime (61491413).

It can be written as a sum of positive squares in only one way, i.e., 55115776 + 6375625 = 7424^2 + 2525^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61491401 is a prime.

It is a Chen prime.

It is equal to p_3645305 and since 61491401 and 3645305 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (61491421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30745700 + 30745701.

It is an arithmetic number, because the mean of its divisors is an integer number (30745701).

Almost surely, 2^61491401 is an apocalyptic number.

It is an amenable number.

61491401 is a deficient number, since it is larger than the sum of its proper divisors (1).

61491401 is an equidigital number, since it uses as much as digits as its factorization.

61491401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 61491401 is about 7841.6452992978. The cubic root of 61491401 is about 394.7039409487.

The spelling of 61491401 in words is "sixty-one million, four hundred ninety-one thousand, four hundred one".