1265901980 has 48 divisors (see below), whose sum is σ = 3198074880. Its totient is φ = 411179328.

The previous prime is 1265901977. The next prime is 1265902003. The reversal of 1265901980 is 891095621.

It is a happy number.

1265901980 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

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, 235292 + ... + 240611.

It is an arithmetic number, because the mean of its divisors is an integer number (66626560).

Almost surely, 2^1265901980 is an apocalyptic number.

1265901980 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1265901980 is an abundant number, since it is smaller than the sum of its proper divisors (1932172900).

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

1265901980 is a wasteful number, since it uses less digits than its factorization.

1265901980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 475938 (or 475936 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 41.

The square root of 1265901980 is about 35579.5162980050. The cubic root of 1265901980 is about 1081.7660804759.

The spelling of 1265901980 in words is "one billion, two hundred sixty-five million, nine hundred one thousand, nine hundred eighty".