61145431 has 4 divisors (see below), whose sum is σ = 63803952. Its totient is φ = 58486912.

The previous prime is 61145419. The next prime is 61145437. The reversal of 61145431 is 13454116.

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

It is a cyclic number.

It is not a de Polignac number, because 61145431 - 2⁷ = 61145303 is a prime.

It is a super-2 number, since 2×61145431² = 7477527464351522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 61145396 and 61145405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61145437) 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, 1329226 + ... + 1329271.

It is an arithmetic number, because the mean of its divisors is an integer number (15950988).

Almost surely, 2^61145431 is an apocalyptic number.

61145431 is a deficient number, since it is larger than the sum of its proper divisors (2658521).

61145431 is a wasteful number, since it uses less digits than its factorization.

61145431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2658520.

The product of its digits is 1440, while the sum is 25.

The square root of 61145431 is about 7819.5543990690. The cubic root of 61145431 is about 393.9623053943.

Adding to 61145431 its reverse (13454116), we get a palindrome (74599547).

The spelling of 61145431 in words is "sixty-one million, one hundred forty-five thousand, four hundred thirty-one".