61291213 has 2 divisors, whose sum is σ = 61291214. Its totient is φ = 61291212.

The previous prime is 61291199. The next prime is 61291249. The reversal of 61291213 is 31219216.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 49744809 + 11546404 = 7053^2 + 3398^2 .

It is a cyclic number.

It is not a de Polignac number, because 61291213 - 2¹³ = 61283021 is a prime.

It is a super-2 number, since 2×61291213² = 7513225582022738, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61291253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30645606 + 30645607.

It is an arithmetic number, because the mean of its divisors is an integer number (30645607).

Almost surely, 2^61291213 is an apocalyptic number.

It is an amenable number.

61291213 is a deficient number, since it is larger than the sum of its proper divisors (1).

61291213 is an equidigital number, since it uses as much as digits as its factorization.

61291213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 648, while the sum is 25.

The square root of 61291213 is about 7828.8704804716. The cubic root of 61291213 is about 394.2751498642.

It can be divided in two parts, 61291 and 213, that added together give a square (61504 = 248²).

The spelling of 61291213 in words is "sixty-one million, two hundred ninety-one thousand, two hundred thirteen".