61520413 has 4 divisors (see below), whose sum is σ = 62129628. Its totient is φ = 60911200.

The previous prime is 61520411. The next prime is 61520419. The reversal of 61520413 is 31402516.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 49871844 + 11648569 = 7062^2 + 3413^2 .

It is a cyclic number.

It is not a de Polignac number, because 61520413 - 2¹ = 61520411 is a prime.

It is a super-2 number, since 2×61520413² = 7569522431381138, which contains 22 as substring.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61520411) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 304456 + ... + 304657.

It is an arithmetic number, because the mean of its divisors is an integer number (15532407).

Almost surely, 2^61520413 is an apocalyptic number.

It is an amenable number.

61520413 is a deficient number, since it is larger than the sum of its proper divisors (609215).

61520413 is a wasteful number, since it uses less digits than its factorization.

61520413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 609214.

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 61520413 is about 7843.4949480445. The cubic root of 61520413 is about 394.7660057259.

Adding to 61520413 its reverse (31402516), we get a palindrome (92922929).

The spelling of 61520413 in words is "sixty-one million, five hundred twenty thousand, four hundred thirteen".