1581364736 has 40 divisors (see below), whose sum is σ = 3611026320. Its totient is φ = 677726208.

The previous prime is 1581364691. The next prime is 1581364781. The reversal of 1581364736 is 6374631851.

It is an interprime number because it is at equal distance from previous prime (1581364691) and next prime (1581364781).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 217031 + ... + 224198.

It is an arithmetic number, because the mean of its divisors is an integer number (90275658).

Almost surely, 2^1581364736 is an apocalyptic number.

1581364736 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1581364736 is an abundant number, since it is smaller than the sum of its proper divisors (2029661584).

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

1581364736 is an frugal number, since it uses more digits than its factorization.

1581364736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441254 (or 441238 counting only the distinct ones).

The product of its digits is 362880, while the sum is 44.

The square root of 1581364736 is about 39766.3769534012. The cubic root of 1581364736 is about 1165.0485310758.

The spelling of 1581364736 in words is "one billion, five hundred eighty-one million, three hundred sixty-four thousand, seven hundred thirty-six".