2581405972 has 6 divisors (see below), whose sum is σ = 4517460458. Its totient is φ = 1290702984.

The previous prime is 2581405963. The next prime is 2581405979. The reversal of 2581405972 is 2795041852.

It can be written as a sum of positive squares in only one way, i.e., 1714456836 + 866949136 = 41406^2 + 29444^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2581405979) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322675743 + ... + 322675750.

Almost surely, 2^2581405972 is an apocalyptic number.

It is an amenable number.

2581405972 is a deficient number, since it is larger than the sum of its proper divisors (1936054486).

2581405972 is a wasteful number, since it uses less digits than its factorization.

2581405972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 645351497 (or 645351495 counting only the distinct ones).

The product of its (nonzero) digits is 201600, while the sum is 43.

The square root of 2581405972 is about 50807.5385351426. The cubic root of 2581405972 is about 1371.7830641545.

The spelling of 2581405972 in words is "two billion, five hundred eighty-one million, four hundred five thousand, nine hundred seventy-two".