61978394445 has 16 divisors (see below), whose sum is σ = 108180470592. Its totient is φ = 30050130560.

The previous prime is 61978394411. The next prime is 61978394461. The reversal of 61978394445 is 54449387916.

It is not a de Polignac number, because 61978394445 - 2⁶ = 61978394381 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 187813152 + ... + 187813481.

It is an arithmetic number, because the mean of its divisors is an integer number (6761279412).

Almost surely, 2^61978394445 is an apocalyptic number.

It is an amenable number.

61978394445 is a deficient number, since it is larger than the sum of its proper divisors (46202076147).

61978394445 is a wasteful number, since it uses less digits than its factorization.

61978394445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 375626652.

The product of its digits is 26127360, while the sum is 60.

The spelling of 61978394445 in words is "sixty-one billion, nine hundred seventy-eight million, three hundred ninety-four thousand, four hundred forty-five".