61421540 has 48 divisors (see below), whose sum is σ = 134206464. Its totient is φ = 23587200.

The previous prime is 61421453. The next prime is 61421573. The reversal of 61421540 is 4512416.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 97025 + ... + 97655.

It is an arithmetic number, because the mean of its divisors is an integer number (2795968).

Almost surely, 2^61421540 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61421540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (67103232).

61421540 is an abundant number, since it is smaller than the sum of its proper divisors (72784924).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61421540 is a wasteful number, since it uses less digits than its factorization.

61421540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 828 (or 826 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 61421540 is about 7837.1895472803. The cubic root of 61421540 is about 394.5544085984.

Adding to 61421540 its reverse (4512416), we get a palindrome (65933956).

The spelling of 61421540 in words is "sixty-one million, four hundred twenty-one thousand, five hundred forty".