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31997952 = 21432731
BaseRepresentation
bin111101000010…
…0000000000000
32020012122221100
41322010000000
531142413302
63101454400
7535656330
oct172040000
966178840
1031997952
1117075598
12a871400
1368244cc
14436d0c0
152c20d1c
hex1e84000

31997952 has 180 divisors, whose sum is σ = 109048576. Its totient is φ = 8847360.

The previous prime is 31997909. The next prime is 31997963. The reversal of 31997952 is 25979913.

It is a happy number.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 31997898 and 31997907.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1032177 + ... + 1032207.

Almost surely, 231997952 is an apocalyptic number.

31997952 is a gapful number since it is divisible by the number (32) 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 31997952, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (54524288).

31997952 is an abundant number, since it is smaller than the sum of its proper divisors (77050624).

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

31997952 is an equidigital number, since it uses as much as digits as its factorization.

31997952 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72 (or 43 counting only the distinct ones).

The product of its digits is 153090, while the sum is 45.

The square root of 31997952 is about 5656.6732272600. The cubic root of 31997952 is about 317.4734373380.

The spelling of 31997952 in words is "thirty-one million, nine hundred ninety-seven thousand, nine hundred fifty-two".