61551134400 has 252 divisors, whose sum is σ = 234909545928. Its totient is φ = 14068776960.

The previous prime is 61551134377. The next prime is 61551134431. The reversal of 61551134400 is 443115516.

It is a happy number.

61551134400 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 104352 + ... + 366048.

Almost surely, 2^61551134400 is an apocalyptic number.

61551134400 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61551134400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (117454772964).

61551134400 is an abundant number, since it is smaller than the sum of its proper divisors (173358411528).

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

61551134400 is a wasteful number, since it uses less digits than its factorization.

61551134400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 261736 (or 261714 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 30.

Adding to 61551134400 its reverse (443115516), we get a palindrome (61994249916).

The spelling of 61551134400 in words is "sixty-one billion, five hundred fifty-one million, one hundred thirty-four thousand, four hundred".