61243231431 has 4 divisors (see below), whose sum is σ = 81657641912. Its totient is φ = 40828820952.

The previous prime is 61243231429. The next prime is 61243231447. The reversal of 61243231431 is 13413234216.

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

It is not a de Polignac number, because 61243231431 - 2¹ = 61243231429 is a prime.

It is a super-2 number, since 2×61243231431² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61243231421) 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, 10207205236 + ... + 10207205241.

It is an arithmetic number, because the mean of its divisors is an integer number (20414410478).

Almost surely, 2^61243231431 is an apocalyptic number.

61243231431 is a deficient number, since it is larger than the sum of its proper divisors (20414410481).

61243231431 is a wasteful number, since it uses less digits than its factorization.

61243231431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20414410480.

The product of its digits is 10368, while the sum is 30.

Adding to 61243231431 its reverse (13413234216), we get a palindrome (74656465647).

The spelling of 61243231431 in words is "sixty-one billion, two hundred forty-three million, two hundred thirty-one thousand, four hundred thirty-one".