61621517 has 2 divisors, whose sum is σ = 61621518. Its totient is φ = 61621516.

The previous prime is 61621507. The next prime is 61621589. The reversal of 61621517 is 71512616.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 57320041 + 4301476 = 7571^2 + 2074^2 .

It is a cyclic number.

It is not a de Polignac number, because 61621517 - 2¹⁸ = 61359373 is a prime.

It is a super-2 number, since 2×61621517² = 7594422714762578, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 61621517.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61621507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30810758 + 30810759.

It is an arithmetic number, because the mean of its divisors is an integer number (30810759).

Almost surely, 2^61621517 is an apocalyptic number.

It is an amenable number.

61621517 is a deficient number, since it is larger than the sum of its proper divisors (1).

61621517 is an equidigital number, since it uses as much as digits as its factorization.

61621517 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2520, while the sum is 29.

The square root of 61621517 is about 7849.9373882853. The cubic root of 61621517 is about 394.9821430799.

The spelling of 61621517 in words is "sixty-one million, six hundred twenty-one thousand, five hundred seventeen".