61278439902 has 16 divisors (see below), whose sum is σ = 122880253440. Its totient is φ = 20372251032.

The previous prime is 61278439883. The next prime is 61278439907. The reversal of 61278439902 is 20993487216.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61278439907) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13471438 + ... + 13475985.

It is an arithmetic number, because the mean of its divisors is an integer number (7680015840).

Almost surely, 2^61278439902 is an apocalyptic number.

61278439902 is an abundant number, since it is smaller than the sum of its proper divisors (61601813538).

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

61278439902 is a wasteful number, since it uses less digits than its factorization.

61278439902 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26947807.

The product of its (nonzero) digits is 1306368, while the sum is 51.

The spelling of 61278439902 in words is "sixty-one billion, two hundred seventy-eight million, four hundred thirty-nine thousand, nine hundred two".