61431523 has 4 divisors (see below), whose sum is σ = 65045160. Its totient is φ = 57817888.

The previous prime is 61431511. The next prime is 61431527. The reversal of 61431523 is 32513416.

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 61431523 - 2⁹ = 61431011 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61431527) 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, 1806793 + ... + 1806826.

It is an arithmetic number, because the mean of its divisors is an integer number (16261290).

Almost surely, 2^61431523 is an apocalyptic number.

61431523 is a deficient number, since it is larger than the sum of its proper divisors (3613637).

61431523 is a wasteful number, since it uses less digits than its factorization.

61431523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3613636.

The product of its digits is 2160, while the sum is 25.

The square root of 61431523 is about 7837.8264206347. The cubic root of 61431523 is about 394.5757834195.

Adding to 61431523 its reverse (32513416), we get a palindrome (93944939).

The spelling of 61431523 in words is "sixty-one million, four hundred thirty-one thousand, five hundred twenty-three".