1021381632 has 198 divisors, whose sum is σ = 3122747628. Its totient is φ = 321490944.

The previous prime is 1021381619. The next prime is 1021381639. The reversal of 1021381632 is 2361831201.

It is a happy number.

1021381632 is a `hidden beast` number, since 1 + 0 + 21 + 3 + 8 + 1 + 632 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 1021381596 and 1021381605.

It is not an unprimeable number, because it can be changed into a prime (1021381639) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 3326823 + ... + 3327129.

Almost surely, 2^1021381632 is an apocalyptic number.

1021381632 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1021381632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1561373814).

1021381632 is an abundant number, since it is smaller than the sum of its proper divisors (2101365996).

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

1021381632 is a wasteful number, since it uses less digits than its factorization.

1021381632 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 371 (or 331 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 1021381632 is about 31959.0618135139. The cubic root of 1021381632 is about 1007.0770084694.

The spelling of 1021381632 in words is "one billion, twenty-one million, three hundred eighty-one thousand, six hundred thirty-two".