1387641525 has 48 divisors (see below), whose sum is σ = 2380050048. Its totient is φ = 712800000.

The previous prime is 1387641511. The next prime is 1387641533. The reversal of 1387641525 is 5251467831.

It is a happy number.

It is not a de Polignac number, because 1387641525 - 2⁴ = 1387641509 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 277800 + ... + 282750.

It is an arithmetic number, because the mean of its divisors is an integer number (49584376).

Almost surely, 2^1387641525 is an apocalyptic number.

1387641525 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1387641525 is a deficient number, since it is larger than the sum of its proper divisors (992408523).

1387641525 is a wasteful number, since it uses less digits than its factorization.

1387641525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5102 (or 5097 counting only the distinct ones).

The product of its digits is 201600, while the sum is 42.

The square root of 1387641525 is about 37251.0607231526. The cubic root of 1387641525 is about 1115.3874728333.

The spelling of 1387641525 in words is "one billion, three hundred eighty-seven million, six hundred forty-one thousand, five hundred twenty-five".