61421216540 has 24 divisors (see below), whose sum is σ = 129464062560. Its totient is φ = 24477151808.

The previous prime is 61421216539. The next prime is 61421216551. The reversal of 61421216540 is 4561212416.

It is a junction number, because it is equal to n+sod(n) for n = 61421216497 and 61421216506.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5702912 + ... + 5713671.

It is an arithmetic number, because the mean of its divisors is an integer number (5394335940).

Almost surely, 2^61421216540 is an apocalyptic number.

It is an amenable number.

61421216540 is an abundant number, since it is smaller than the sum of its proper divisors (68042846020).

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

61421216540 is a wasteful number, since it uses less digits than its factorization.

61421216540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11416861 (or 11416859 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 32.

Adding to 61421216540 its reverse (4561212416), we get a palindrome (65982428956).

The spelling of 61421216540 in words is "sixty-one billion, four hundred twenty-one million, two hundred sixteen thousand, five hundred forty".