61339299840 has 1664 divisors, whose sum is σ = 285345607680. Its totient is φ = 12145655808.

The previous prime is 61339299809. The next prime is 61339299841. The reversal of 61339299840 is 4899293316.

It is a tau number, because it is divible by the number of its divisors (1664).

It is a super-2 number, since 2×61339299840² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61339299841) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1157345254 + ... + 1157345306.

Almost surely, 2^61339299840 is an apocalyptic number.

61339299840 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 61339299840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (142672803840).

61339299840 is an abundant number, since it is smaller than the sum of its proper divisors (224006307840).

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

61339299840 is a wasteful number, since it uses less digits than its factorization.

61339299840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134 (or 106 counting only the distinct ones).

The product of its (nonzero) digits is 2519424, while the sum is 54.

The spelling of 61339299840 in words is "sixty-one billion, three hundred thirty-nine million, two hundred ninety-nine thousand, eight hundred forty".