61211501440 has 32 divisors (see below), whose sum is σ = 146333747160. Its totient is φ = 24484600320.

The previous prime is 61211501387. The next prime is 61211501443. The reversal of 61211501440 is 4410511216.

It is a tau number, because it is divible by the number of its divisors (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61211501443) 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, 47820846 + ... + 47822125.

Almost surely, 2^61211501440 is an apocalyptic number.

It is an amenable number.

61211501440 is an abundant number, since it is smaller than the sum of its proper divisors (85122245720).

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

61211501440 is an equidigital number, since it uses as much as digits as its factorization.

61211501440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95642990 (or 95642978 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 25.

The spelling of 61211501440 in words is "sixty-one billion, two hundred eleven million, five hundred one thousand, four hundred forty".