1381257620 has 48 divisors (see below), whose sum is σ = 2977793280. Its totient is φ = 537930624.

The previous prime is 1381257613. The next prime is 1381257623. The reversal of 1381257620 is 267521831.

It is a happy number.

It is a super-2 number, since 2×1381257620² = 3815745225616128800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1381257623) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 181451 + ... + 188909.

It is an arithmetic number, because the mean of its divisors is an integer number (62037360).

Almost surely, 2^1381257620 is an apocalyptic number.

1381257620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1381257620 is an abundant number, since it is smaller than the sum of its proper divisors (1596535660).

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

1381257620 is a wasteful number, since it uses less digits than its factorization.

1381257620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7712 (or 7710 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 35.

The square root of 1381257620 is about 37165.2743834887. The cubic root of 1381257620 is about 1113.6743802796.

The spelling of 1381257620 in words is "one billion, three hundred eighty-one million, two hundred fifty-seven thousand, six hundred twenty".