61511413 has 4 divisors (see below), whose sum is σ = 61528780. Its totient is φ = 61494048.

The previous prime is 61511399. The next prime is 61511431. The reversal of 61511413 is 31411516.

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 23590449 + 37920964 = 4857^2 + 6158^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61511413 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61511213) 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, 1248 + ... + 11161.

It is an arithmetic number, because the mean of its divisors is an integer number (15382195).

Almost surely, 2^61511413 is an apocalyptic number.

It is an amenable number.

61511413 is a deficient number, since it is larger than the sum of its proper divisors (17367).

61511413 is a wasteful number, since it uses less digits than its factorization.

61511413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17366.

The product of its digits is 360, while the sum is 22.

The square root of 61511413 is about 7842.9212032252. The cubic root of 61511413 is about 394.7467542983.

Adding to 61511413 its reverse (31411516), we get a palindrome (92922929).

The spelling of 61511413 in words is "sixty-one million, five hundred eleven thousand, four hundred thirteen".