61621752215720 has 32 divisors (see below), whose sum is σ = 138655487214720. Its totient is φ = 24647537378880.

The previous prime is 61621752215593. The next prime is 61621752215753. The reversal of 61621752215720 is 2751225712616.

It is a happy number.

It is a super-2 number, since 2×61621752215720² (a number of 28 digits) contains 22 as substring.

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, 35501372 + ... + 37196651.

It is an arithmetic number, because the mean of its divisors is an integer number (4332983975460).

Almost surely, 2^{61621752215720} is an apocalyptic number.

It is an amenable number.

61621752215720 is an abundant number, since it is smaller than the sum of its proper divisors (77033734999000).

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

61621752215720 is a wasteful number, since it uses less digits than its factorization.

61621752215720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72719225 (or 72719221 counting only the distinct ones).

The product of its (nonzero) digits is 705600, while the sum is 47.

The spelling of 61621752215720 in words is "sixty-one trillion, six hundred twenty-one billion, seven hundred fifty-two million, two hundred fifteen thousand, seven hundred twenty".